Merge branch 'master' into feat/issue-637-timeline-model

Review #526 found that event_type reached the serialized timeline payload
without crossing the redaction/validation boundary every other free-text
field on the same event crosses. A synthetic secret-shaped 40-hex canary
was redacted through message but survived verbatim through event_type on
the same control-plane record.

CTH heading path: CTH_TYPES is now the single authority for what a CTH
type may be. canonical_thread_handoff.is_known_cth_type() is that
authority, used by format_cth_body (write), assess_cth_comment (assess),
and now the read path too; parse_cth_comment reports membership as
cth_type_known and stays total. adapt_cth_comments serializes
handoff:<type> only for a declared type and otherwise emits the constant
handoff:unrecognized, so arbitrary, malformed, secret-shaped, or
whitespace-manipulated heading content never becomes an event_type.

Control-plane path: a stored event_type is treated as source data.
_safe_cp_event_type accepts only an ordinary identifier that is not a
bare secret-shaped hex run and that a redaction pass leaves unchanged;
anything else fails closed to the constant unsafe:redacted and marks the
event sensitive. The value is never emitted verbatim, never partially
sanitized, and never rewritten into a different valid-looking type.

Remaining serialized-field audit: event_key ids must be plain numeric
identifiers, the CTH adapter refuses a scope it cannot express, per-source
failure reasons are redacted (they can quote an authenticated fetch error),
and echoed scope/filter values are guarded so reflection is not a bypass.

Legitimate values are preserved: every declared CTH type, the real
producer types (assigned, lease_released, lease_adopted,
dependency_edge_state_change, allocation, pr.opened, lease.renew), and
the existing issue, PR, evidence, and full-SHA references.

Tests seed the canary independently through both event_type paths with a
benign message, so message redaction cannot be why they pass; each
inspects event_type directly, asserts the canary is absent from the
complete serialized payload, and asserts scan_for_secrets finds nothing.

tests/test_webui_timeline.py 64 passed, 15 subtests
pytest -k webui 362 passed, 285 subtests
pytest -k redact 79 passed
tests/test_canonical_thread_handoff.py tests/test_control_plane_db.py 29 passed

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

allocator_service.py

@@ -53,6 +53,8 @@ OUTCOME_CANDIDATE_SET_DRIFT = "candidate_set_drift"
 SKIP_CLAIMED_BY_OTHER_SESSION = "claimed_by_other_session"
 # #776: controller-supplied pre-rank exclusion.
 SKIP_EXCLUDED_BY_CONTROLLER = "excluded_by_controller"
+# #844: epic / child-only implementation container (pre-rank).
+SKIP_EPIC_OR_CHILD_ONLY_CONTAINER = "epic_or_child_only_container"
 
 # Ownership verdicts for a live claim on a candidate (#765).
 OWNERSHIP_OWN = "own"
@@ -130,6 +132,39 @@ ROLE_ACTIONS: dict[str, tuple[tuple[str, ...], tuple[str, ...]]] = {
 }
 
 
+# Body phrases that prove an issue is an implementation container, not a
+# unit of direct author work (#844). Matched case-insensitively against the
+# issue body. Title alone is never sufficient (ordinary issues may mention
+# "epic" incidentally).
+_CHILD_ONLY_BODY_MARKERS: tuple[str, ...] = (
+    "implementation is delivered via child issues only",
+    "implementation is delivered through child issues only",
+    "implementation is delivered via child issues",
+    "implementation is delivered through child issues",
+    "do not implement product features in this epic",
+    "do not implement product features in this epic issue itself",
+    "no product feature implementation is claimed complete solely on this epic",
+    "implementable child issues remain independently eligible",
+    "owns the product roadmap and linkage",
+    "this epic owns the product roadmap",
+    "coordination container",
+    "child-only container",
+    "implementation is delegated to child",
+)
+
+# Explicit epic / umbrella labels (structured evidence preferred over title).
+_EPIC_LABELS: frozenset[str] = frozenset(
+    {
+        "type:epic",
+        "epic",
+        "kind:epic",
+        "scope:epic",
+        "type:umbrella",
+        "umbrella",
+    }
+)
+
+
 @dataclass
 class WorkCandidate:
     """One assignable Gitea issue or PR presented to the allocator."""
@@ -139,6 +174,7 @@ class WorkCandidate:
     state: str = "open"
     labels: tuple[str, ...] = ()
     title: str = ""
+    body: str = ""
     priority: int = 0
     head_sha: str | None = None
     # Routing signals (callers derive from Gitea / review feedback).
@@ -158,6 +194,7 @@ class WorkCandidate:
         self.labels = tuple(
             str(x).strip().lower() for x in (self.labels or ()) if str(x).strip()
         )
+        self.body = str(self.body or "")
         if self.kind not in WORK_KINDS:
             raise InvalidWorkKindError(
                 f"candidate kind '{self.kind}' is not assignable; only "
@@ -171,6 +208,7 @@ class WorkCandidate:
             "state": self.state,
             "labels": list(self.labels),
             "title": self.title,
+            "body": self.body,
             "priority": self.priority,
             "head_sha": self.head_sha,
             "request_changes_current_head": self.request_changes_current_head,
@@ -184,6 +222,51 @@ class WorkCandidate:
         }
 
 
+def classify_epic_or_child_only_container(
+    c: WorkCandidate,
+) -> tuple[bool, str | None]:
+    """Return whether *c* is an epic / child-only implementation container (#844).
+
+    Exclusion uses structured evidence first (labels, body scope language).
+    A bare title containing the word "epic" is **not** enough — ordinary
+    implementable issues may mention epics incidentally. A title that is
+    explicitly prefixed ``Epic:`` only counts when the body also proves
+    child-only / no-direct-implementation scope (or an epic label is present).
+
+    PRs are never classified as containers here (they already have a head).
+    """
+    if c.kind != "issue":
+        return False, None
+
+    labels = set(c.labels)
+    epic_label = sorted(labels & _EPIC_LABELS)
+    body_l = (c.body or "").lower()
+    title = (c.title or "").strip()
+    title_l = title.lower()
+
+    body_hits = [m for m in _CHILD_ONLY_BODY_MARKERS if m in body_l]
+    title_epic_prefix = title_l.startswith("epic:") or title_l.startswith("epic ")
+
+    if epic_label:
+        detail = f"label={epic_label[0]}"
+        if body_hits:
+            detail = f"{detail}; body_marker={body_hits[0]!r}"
+        return True, detail
+
+    if body_hits:
+        # Body proves child-only / umbrella scope. Title "Epic:" is corroborating
+        # but not required — containers without the word still exclude.
+        detail = f"body_marker={body_hits[0]!r}"
+        if title_epic_prefix:
+            detail = f"title_epic_prefix; {detail}"
+        return True, detail
+
+    # Title-only "Epic:" without body scope evidence is insufficient (#844 AC:
+    # eligibility does not rely solely on the word "Epic" in a title).
+    # Similarly, incidental "epic" mid-title without markers stays eligible.
+    return False, None
+
+
 @dataclass
 class SkipRecord:
     kind: str
@@ -850,7 +933,8 @@ def allocate_next_work(
     ownership_defects: list[dict[str, Any]] = []
     controller_excluded: list[dict[str, Any]] = []
 
-    # #776 AC2: remove excluded numbers *before* ranking / selection / lease.
+    # #776 AC2 + #844: remove excluded numbers *and* epic/child-only containers
+    # *before* ranking / selection / lease so they never receive assignments.
     rankable: list[WorkCandidate] = []
     for c in candidates:
         if int(c.number) in exclude_set:
@@ -929,6 +1013,23 @@ def allocate_next_work(
                     },
                 }
             continue
+        # #844: epics / child-only containers are never direct implement targets.
+        is_container, container_detail = classify_epic_or_child_only_container(c)
+        if is_container:
+            detail = container_detail or "epic or child-only container"
+            reason = (
+                f"{c.kind}#{c.number} {SKIP_EPIC_OR_CHILD_ONLY_CONTAINER}: "
+                f"{detail}; implementation is delegated to child issues"
+            )
+            skipped.append(
+                SkipRecord(
+                    c.kind,
+                    c.number,
+                    reason,
+                    SKIP_EPIC_OR_CHILD_ONLY_CONTAINER,
+                )
+            )
+            continue
         rankable.append(c)
 
     ordered = sort_candidates(rankable)
@@ -1115,6 +1216,12 @@ def allocate_next_work(
             "reasons": [
                 "dry-run only (apply=false); no assignment/lease created — "
                 "call again with apply=true to reserve via control-plane DB"
+                + (
+                    "; after apply, the required-role worker consumes via "
+                    "gitea_adopt_workflow_lease (#843)"
+                    if mode == ALLOCATION_MODE_CROSS_ROLE and expected_role != role_norm
+                    else ""
+                )
             ],
             "skipped": [s.as_dict() for s in skipped],
             "terminal_pr": terminal_pr,
@@ -1146,6 +1253,9 @@ def allocate_next_work(
     # Atomic reserve via #613 substrate.
     ttl = lease_ttl_seconds if lease_ttl_seconds is not None else None
     try:
+        cross_role_handoff = (
+            mode == ALLOCATION_MODE_CROSS_ROLE and lease_role != role_norm
+        )
         kwargs: dict[str, Any] = {
             "session_id": session_id,
             "role": lease_role,
@@ -1157,7 +1267,8 @@ def allocate_next_work(
             "expected_head_sha": selected.head_sha,
             "allowed_actions": allowed,
             "forbidden_actions": forbidden,
-            "phase": "allocated",
+            # #843: mark cross-role allocations as awaiting independent consume
+            "phase": "awaiting_handoff" if cross_role_handoff else "allocated",
         }
         if ttl is not None:
             kwargs["lease_ttl_seconds"] = int(ttl)
@@ -1237,7 +1348,52 @@ def allocate_next_work(
         "lease_role": lease_role,
         "source": "control_plane_db.assign_and_lease",
     }
-    return {
+    consume_allocation = None
+    if cross_role_handoff and result.lease_id:
+        # Durable handoff marker so independent required-role workers can
+        # consume without sharing the controller session (#843).
+        handoff_prov = {
+            "cross_role_handoff": True,
+            "handoff_status": "pending",
+            "allocating_session_id": session_id,
+            "allocating_role": role_norm,
+            "required_role": expected_role,
+            "required_profile": selection["required_profile"],
+            "required_namespace": selection["required_namespace"],
+            "assignment_id": result.assignment_id,
+            "lease_id": result.lease_id,
+            "allocation_mode": mode,
+            "adopted_by_session_id": None,
+        }
+        try:
+            db.attach_lease_provenance(result.lease_id, handoff_prov)
+        except ControlPlaneError:
+            # Still return assignment evidence; consume path may be unavailable
+            handoff_prov["attach_failed"] = True
+        consume_allocation = {
+            "tool": "gitea_adopt_workflow_lease",
+            "lease_id": result.lease_id,
+            "assignment_id": result.assignment_id,
+            "required_role": expected_role,
+            "required_profile": selection["required_profile"],
+            "required_namespace": selection["required_namespace"],
+            "handoff_status": "pending",
+            "controller_session_required": False,
+            "instructions": (
+                f"From an independent {expected_role} session "
+                f"({selection['required_namespace']} / "
+                f"{selection['required_profile']}), call "
+                f"gitea_adopt_workflow_lease(lease_id={result.lease_id!r}) "
+                "to consume this controller allocation. The allocating "
+                "controller process does not need to remain alive. Wrong-role "
+                "and second-adoption attempts fail closed."
+            ),
+        }
+        lease_proof["cross_role_handoff"] = True
+        lease_proof["handoff_status"] = "pending"
+        lease_proof["consume_tool"] = "gitea_adopt_workflow_lease"
+
+    out = {
         "success": True,
         "outcome": OUTCOME_ASSIGNED,
         "apply": True,
@@ -1271,8 +1427,17 @@ def allocate_next_work(
             "lease_role": lease_role,
             "lease_proof": lease_proof,
             "selection_policy": SELECTION_POLICY,
+            "cross_role_handoff": bool(cross_role_handoff),
         },
-        "next_valid_command": _next_command(lease_role, selected),
+        "next_valid_command": (
+            (
+                f"consume lease {result.lease_id} via gitea_adopt_workflow_lease "
+                f"as {expected_role}, then "
+            )
+            + _next_command(lease_role, selected)
+            if cross_role_handoff
+            else _next_command(lease_role, selected)
+        ),
         "substrate": "control_plane_db",
         "file_lock_only": False,
         "comment_lease_only": False,
@@ -1287,9 +1452,14 @@ def allocate_next_work(
         "downstream_note": (
             "#612 incident bridge remains downstream of #600; "
             "allocator never assigns raw monitoring incidents; "
-            "controller routes only under cross_role (#840)"
+            "controller routes only under cross_role (#840); "
+            "cross-role assignments are consumable by independent "
+            "required-role workers via gitea_adopt_workflow_lease (#843)"
         ),
     }
+    if consume_allocation is not None:
+        out["consume_allocation"] = consume_allocation
+    return out
 
 
 def _next_command(role: str, c: WorkCandidate) -> str:
@@ -1341,6 +1511,7 @@ def candidate_from_dict(data: dict[str, Any]) -> WorkCandidate:
         state=str(data.get("state") or "open"),
         labels=tuple(data.get("labels") or ()),
         title=str(data.get("title") or ""),
+        body=str(data.get("body") or ""),
         priority=priority,
         head_sha=data.get("head_sha"),
         request_changes_current_head=bool(data.get("request_changes_current_head")),

canonical_thread_handoff.py

@@ -46,6 +46,17 @@ _FIELD_RE = re.compile(
 )
 
 
+def is_known_cth_type(value: str | None) -> bool:
+    """True when *value* is a declared member of the :data:`CTH_TYPES` contract.
+
+    ``CTH_TYPES`` is the single authority for what a CTH type may be. The
+    heading a comment carries is free text, so a *read* path that turns a parsed
+    type into something durable — a serialized field, a routing decision — must
+    check membership here rather than trust the parse or keep a list of its own.
+    """
+    return (value or "").strip() in CTH_TYPES
+
+
 def format_cth_body(
     *,
     cth_type: str,
@@ -60,7 +71,7 @@ def format_cth_body(
 ) -> str:
     """Render a canonical CTH comment body."""
     normalized_type = (cth_type or "").strip()
-    if normalized_type not in CTH_TYPES:
+    if not is_known_cth_type(normalized_type):
         raise ValueError(
             f"unknown CTH type '{cth_type}'; expected one of {sorted(CTH_TYPES)}"
         )
@@ -101,6 +112,12 @@ def parse_cth_comment(body: str) -> dict[str, Any] | None:
         fields[key] = match.group(2).strip()
     return {
         "cth_type": cth_type,
+        # The heading capture is unconstrained free text, so the parse states
+        # whether it satisfies the CTH_TYPES contract instead of leaving every
+        # reader to decide (or forget). Parsing stays total — an unknown type is
+        # still parsed and reported, never raised on — but a reader that turns
+        # the type into a durable value can now tell the two apart.
+        "cth_type_known": is_known_cth_type(cth_type),
         "fields": fields,
         "raw_body": text,
     }
@@ -119,7 +136,7 @@ def assess_cth_comment(body: str) -> dict[str, Any]:
         }
 
     cth_type = parsed.get("cth_type") or ""
-    if cth_type not in CTH_TYPES:
+    if not is_known_cth_type(cth_type):
         reasons.append(
             f"unknown CTH type '{cth_type}'; expected one of {sorted(CTH_TYPES)}"
         )

control_plane_db.py

@@ -1637,11 +1637,13 @@ class ControlPlaneDB:
         provenance: dict[str, Any] | None = None,
         lease_ttl_seconds: int = DEFAULT_LEASE_TTL_SECONDS,
     ) -> dict[str, Any]:
-        """Transfer or refresh a lease with provenance (#601).
+        """Transfer or refresh a lease with provenance (#601 / #843).
 
         * Same owner + active → refresh (owner-resume).
+        * Cross-role handoff pending + matching required role → atomic consume
+          (even while the allocating controller session still "owns" the lease).
         * Expired/abandoned/released → create new assignment+lease with provenance.
-        * Active foreign → raise ForeignLeaseError (never silent steal).
+        * Active foreign (non-handoff) → raise ForeignLeaseError (never silent steal).
         """
         now = _utc_now()
         now_s = _ts(now)
@@ -1677,7 +1679,35 @@ class ControlPlaneDB:
                 status = "expired"
 
             owner = lease["session_id"]
-            if status == "active" and owner != adopter_session_id:
+            # Parse durable provenance for cross-role handoff consume (#843).
+            lease_prov: dict[str, Any] = {}
+            if "provenance_json" in lease.keys() and lease["provenance_json"]:
+                try:
+                    loaded = json.loads(lease["provenance_json"])
+                    if isinstance(loaded, dict):
+                        lease_prov = loaded
+                except (TypeError, json.JSONDecodeError):
+                    lease_prov = {}
+            handoff_pending = bool(lease_prov.get("cross_role_handoff")) and (
+                str(lease_prov.get("handoff_status") or "pending").strip().lower()
+                == "pending"
+            )
+            already_adopted = bool(
+                (lease["adopted_by_session_id"] if "adopted_by_session_id" in lease.keys() else None)
+                or lease_prov.get("adopted_by_session_id")
+            )
+            required_role = str(
+                lease_prov.get("required_role") or lease["role"] or ""
+            ).strip().lower()
+            adopter_role = (role or "").strip().lower()
+            cross_role_consume = (
+                handoff_pending
+                and not already_adopted
+                and status == "active"
+                and owner != adopter_session_id
+            )
+
+            if status == "active" and owner != adopter_session_id and not cross_role_consume:
                 raise ForeignLeaseError(
                     f"cannot adopt active foreign lease {lease_id} owned by {owner}"
                 )
@@ -1761,6 +1791,142 @@ class ControlPlaneDB:
                     "reasons": ["owner-resume: refreshed lease with provenance"],
                 }
 
+            # #843: controller→required-role handoff consume (atomic, same lease_id)
+            if cross_role_consume:
+                if not required_role:
+                    raise ControlPlaneError(
+                        f"cross-role handoff lease {lease_id} missing required_role"
+                    )
+                if adopter_role != required_role:
+                    raise ForeignLeaseError(
+                        f"wrong role for cross-role handoff consume: "
+                        f"required={required_role} adopter={adopter_role or 'none'} "
+                        f"(fail closed)"
+                    )
+                # CAS: only transfer if still owned by allocating session and unadopted
+                cols = self._lease_columns(conn)
+                adopted_col_null = (
+                    "(adopted_by_session_id IS NULL OR adopted_by_session_id = '')"
+                    if "adopted_by_session_id" in cols
+                    else "1=1"
+                )
+                cas = conn.execute(
+                    f"""
+                    UPDATE leases
+                    SET session_id = ?,
+                        heartbeat_at = ?,
+                        expires_at = ?,
+                        phase = ?,
+                        role = ?
+                    WHERE lease_id = ?
+                      AND status = 'active'
+                      AND session_id = ?
+                      AND {adopted_col_null}
+                    """,
+                    (
+                        adopter_session_id,
+                        now_s,
+                        expires,
+                        "adopted",
+                        required_role,
+                        lease_id,
+                        owner,
+                    ),
+                )
+                if cas.rowcount != 1:
+                    raise ForeignLeaseError(
+                        f"cross-role handoff consume lost race for lease {lease_id} "
+                        "(already adopted or no longer pending; fail closed)"
+                    )
+                if "adopted_from_session_id" in cols:
+                    conn.execute(
+                        """
+                        UPDATE leases
+                        SET adopted_from_session_id = ?, adopted_by_session_id = ?
+                        WHERE lease_id = ?
+                        """,
+                        (owner, adopter_session_id, lease_id),
+                    )
+                if "worktree_path" in cols and worktree_path:
+                    conn.execute(
+                        "UPDATE leases SET worktree_path = ? WHERE lease_id = ?",
+                        (worktree_path, lease_id),
+                    )
+                if "owner_pid" in cols and owner_pid is not None:
+                    conn.execute(
+                        "UPDATE leases SET owner_pid = ? WHERE lease_id = ?",
+                        (owner_pid, lease_id),
+                    )
+                if "expected_head_sha" in cols and expected_head_sha:
+                    conn.execute(
+                        "UPDATE leases SET expected_head_sha = ? WHERE lease_id = ?",
+                        (expected_head_sha, lease_id),
+                    )
+                # Merge handoff provenance + caller provenance
+                merged = dict(lease_prov)
+                merged.update(provenance or {})
+                merged["cross_role_handoff"] = True
+                merged["handoff_status"] = "adopted"
+                merged["adopted_from_session_id"] = owner
+                merged["adopted_by_session_id"] = adopter_session_id
+                merged["required_role"] = required_role
+                if "provenance_json" in cols:
+                    conn.execute(
+                        "UPDATE leases SET provenance_json = ? WHERE lease_id = ?",
+                        (json.dumps(merged), lease_id),
+                    )
+                # Transfer active assignment ownership atomically
+                asn_cas = conn.execute(
+                    """
+                    UPDATE assignments
+                    SET session_id = ?, role = ?
+                    WHERE lease_id = ? AND status = 'active' AND session_id = ?
+                    """,
+                    (adopter_session_id, required_role, lease_id, owner),
+                )
+                if asn_cas.rowcount < 1:
+                    # Fail closed: assignment must move with the lease
+                    raise ControlPlaneError(
+                        f"cross-role handoff: no active assignment for lease {lease_id} "
+                        f"owned by {owner}"
+                    )
+                lease2 = conn.execute(
+                    "SELECT * FROM leases WHERE lease_id = ?", (lease_id,)
+                ).fetchone()
+                asn = conn.execute(
+                    """
+                    SELECT * FROM assignments
+                    WHERE lease_id = ? AND status = 'active'
+                    ORDER BY created_at DESC LIMIT 1
+                    """,
+                    (lease_id,),
+                ).fetchone()
+                conn.execute(
+                    """
+                    INSERT INTO events(work_item_id, event_type, message, created_at)
+                    VALUES (?, 'lease_adopted', ?, ?)
+                    """,
+                    (
+                        lease["work_item_id"],
+                        f"cross-role handoff: {adopter_session_id} consumed "
+                        f"{lease_id} from {owner} as {required_role}",
+                        now_s,
+                    ),
+                )
+                return {
+                    "outcome": "adopted_cross_role_handoff",
+                    "lease": dict(lease2) if lease2 else dict(lease),
+                    "assignment": dict(asn) if asn else None,
+                    "reasons": [
+                        "cross-role handoff: independent required-role worker consumed "
+                        "controller allocation without abandonment"
+                    ],
+                    "adopted_by_session_id": adopter_session_id,
+                    "adopted_from_session_id": owner,
+                    "required_role": required_role,
+                    "handoff_status": "adopted",
+                }
+
             # Non-active: create new lease + assignment (transfer)
             new_lease_id = f"lease-{uuid.uuid4().hex[:16]}"
             new_asn_id = f"asn-{uuid.uuid4().hex[:16]}"

docs/webui-local-dev.md

@@ -52,7 +52,8 @@ status, onboarding checklist state, and the fail-closed error payloads (#635).
 | Path | Description |
 |------|-------------|
 | `/` | Home / operator overview |
-| `/health` | JSON liveness (`status`, `service`, `mode`, `timestamp`) |
+| `/health` | JSON liveness (`status`, `service`, `mode`, `timestamp`, `uptime_seconds`) |
+| `/api/v1/system/health` | Structured read-only system health (#634) |
 | `/queue` | Live PR and issue queue dashboard (#429) |
 | `/api/queue` | JSON queue export with pagination metadata |
 | `/projects` | Project registry list with status and onboarding progress (#427, #635) |
@@ -73,11 +74,95 @@ status, onboarding checklist state, and the fail-closed error payloads (#635).
 | `/api/actions/{id}/preview` | Mutation ledger preview (GET, read-only) |
 | `/leases` | Lease and collision visibility (#433) |
 | `/api/leases` | JSON lease/collision export |
+| `/sessions` | Phase 1 shell stub — session inventory (backed by #636) |
+| `/inventory` | Phase 1 shell stub — unified inventory (backed by #636) |
+| `/timeline` | Phase 1 shell stub — workflow event timeline |
+| `/policy` | Phase 1 shell stub — capability/role policy placeholder |
+| `/insights` | Phase 1 shell stub — operational insights placeholder |
 
 Most routes are GET-only. POST/PUT/PATCH/DELETE return `405` with
 `read-only-mvp`, except `/audit` and `/api/audit` which accept POST for
 local validator preview only (no Gitea mutations, no server-side storage).
 
+## System health API (#634)
+
+`GET /api/v1/system/health` is the structured, read-only health surface for
+automated readiness checks. It is the first console API under the `/api/v1`
+prefix; the unversioned MVP exports remain as compatibility aliases.
+
+`/health` is unchanged for existing consumers — every MVP key is still present
+— and now also carries `started_at`, `uptime_seconds`, and a
+`system_health_api` pointer. It stays deliberately cheap and runs no dependency
+probe, because answering readiness costs real work.
+
+**Status codes.** `200` when ready, `503` when a required dependency failed or
+was never probed. Automation can branch on the code without parsing the body.
+
+**Query flags.** The Gitea check is a network call, so it is opt-in:
+`GET /api/v1/system/health?deep=1` runs it and caches the result for
+`WEBUI_HEALTH_PROBE_TTL_SECONDS` (default 15s) so dashboard polling does not
+amplify into remote load. Without the flag that probe reports `skipped`.
+
+**Dependencies.** `control_plane_db` and `repository` are required and drive
+readiness. `gitea` is optional: when it fails the overall `status` degrades but
+`readiness.ready` stays true, because local inventory is still serveable. Each
+entry carries `status`, `detail`, `required`, and `latency_ms`.
+
+Two honesty rules are worth knowing before reading the payload:
+
+* `stale_runtime.mutation_safe` is true only when the runtime, checkout, and
+  remote-tracking commits are all known and equal. An unfetched remote is
+  reported as indeterminate, never as safe.
+* `mcp_namespaces` entries are always `unproven`. A web process runs outside
+  the IDE-managed MCP client and cannot invoke a namespace tool, so per #543
+  only a `client_namespace` probe can prove that path.
+
+Sample response (abridged, healthy):
+
+```json
+{
+  "status": "ok",
+  "service": "mcp-control-plane-webui",
+  "mode": "read-only",
+  "api": "/api/v1/system/health",
+  "timestamp": "2026-07-22T11:04:18.512034+00:00",
+  "readiness": { "ready": true, "complete": true, "reasons": [] },
+  "version": {
+    "git_sha": "620ed6e9a9550b8da2ceb82d9ab8744e8920490f",
+    "git_describe": "v1.1.0-898-g620ed6e",
+    "control_plane_schema_version": 4,
+    "python_version": "3.14.5",
+    "known": true
+  },
+  "process": { "started_at": "2026-07-22T10:58:02.114+00:00", "uptime_seconds": 376.4 },
+  "deep_probes_requested": false,
+  "dependencies": [
+    {
+      "name": "control_plane_db",
+      "kind": "sqlite",
+      "status": "ok",
+      "detail": "schema v4 readable",
+      "required": true,
+      "healthy": true,
+      "latency_ms": 1.482,
+      "metadata": { "schema_version": 4, "active_leases": 3 }
+    },
+    { "name": "repository", "kind": "git", "status": "ok", "required": true, "healthy": true },
+    { "name": "gitea", "kind": "http", "status": "skipped", "required": false, "healthy": false }
+  ],
+  "mcp_namespaces": [
+    { "namespace": "gitea-author", "required_tool": "gitea_whoami", "status": "unproven" }
+  ],
+  "stale_runtime": { "stale": false, "determinable": true, "mutation_safe": true, "reasons": [] },
+  "probe_errors": []
+}
+```
+
+No restart, reload, or process-kill control is exposed here: those are Phase 2
+at the earliest, and #630 forbids process-kill recovery outright. Every probe
+opens its subject read-only — the control-plane database is opened through a
+`mode=ro` URI so a health check can never create or migrate a schema.
+
 ## Report audit (#431)
 
 Paste an LLM final report at `/audit` or POST JSON to `/api/audit`. The UI
@@ -153,6 +238,26 @@ health, workflow/schema SHA-256 hashes, and stale-runtime warnings when the
 checkout is behind merged safety-gate changes. Restart guidance links to #420;
 no tokens or MCP restart actions are exposed.
 
+## Application shell — Phase 1 (#638)
+
+The console shell (`webui/layout.py`) renders a grouped navigation driven by a
+single nav-config module, `webui/nav.py`. Nav groups follow the epic #631
+Phase 1 information architecture: **Health, Traffic, Runtime/Sessions,
+Projects, Inventory, Timeline, Policy** (placeholder), and **Insights**
+(placeholder). Live views and Phase 1 placeholders (`stub`) are declared in one
+place so the layout and the route table cannot drift.
+
+The header carries two read-only status badges — an **environment** badge
+(`local` for loopback binds, `remote` otherwise, derived from `WEBUI_HOST`) and
+a **mode: read-only** badge — plus a **Docs** link to this document. No
+privileged action controls are present in the Phase 1 shell.
+
+Not-yet-implemented surfaces (`/sessions`, `/inventory`, `/timeline`,
+`/policy`, `/insights`) resolve to graceful read-only stub pages instead of
+404s; their backing views land in later child issues of #631 (the inventory
+surfaces are backed by #636). Mutating methods on stub routes still fail closed
+with `read-only-mvp`.
+
 ## Deployment boundary (#435)
 
 MVP serves on loopback by default. Binding `0.0.0.0` or `::` is **refused**
@@ -212,6 +317,108 @@ health, workflow/schema SHA-256 hashes, and stale-runtime warnings when the
 checkout is behind merged safety-gate changes. Restart guidance links to #420;
 no tokens or MCP restart actions are exposed.
 
+## Workflow-event timeline (#637)
+
+`GET /api/v1/timeline` is a read-only, versioned aggregation of workflow
+events from every available source into one normalised, filterable stream. It
+is the model layer for the Phase 1 timeline console view (a later child issue
+of #631); this issue ships the schema, adapters, and read API only.
+
+### Schema (versioned)
+
+`webui/timeline.py` declares `TIMELINE_SCHEMA_VERSION` (currently `1`) and the
+frozen `WorkflowEvent` record. Every response carries `schema_version` so a
+consumer can branch on shape. One event:
+
+```json
+{
+  "source": "control_plane",
+  "event_type": "lease.renew",
+  "event_key": "cp:1421",
+  "timestamp": "2026-07-23T02:00:00Z",
+  "actor": null,
+  "role": null,
+  "issue_number": 637,
+  "pr_number": null,
+  "session_id": null,
+  "tool_name": null,
+  "decision": null,
+  "message": "lease renewed",
+  "correlation_id": "issue#637",
+  "evidence_refs": [],
+  "sensitive": true
+}
+```
+
+`event_key` is stable and unique per source (`cp:<event_id>`,
+`cth:<kind>:<number>:<comment_id>`), so pagination and dedup are deterministic.
+
+### Sources and field authority
+
+| Source | Adapter | Authority |
+|---|---|---|
+| Control-plane `events` ⋈ `work_items` | `adapt_cp_events` | `event_type`, `message`, `timestamp`, issue/PR scope come from the CP database, read through a `mode=ro` URI (never creates the DB or runs migrations) |
+| Gitea Canonical Thread Handoff comments | `adapt_cth_comments` | `actor`, `role` (next owner), `decision`, `evidence_refs`, `timestamp` come from the parsed CTH comment body (`canonical_thread_handoff`) |
+
+Handoff comments are thread-scoped: they are only read when the request filters
+by a single `issue` or `pr`. Otherwise the handoff source reports `not run`
+with a reason — it is never rendered as empty-and-healthy. Each source degrades
+independently: an unavailable control-plane DB or a failed comment fetch is a
+`sources[]` entry with `ok:false` and a `reason`, never a dropped timeline.
+
+### Query parameters
+
+`issue`, `pr`, `session` (conjunctive filters); `limit` (default 50, max 500)
+and `offset` for pagination; `remote`, `org`, `repo` to override the default
+registry-project scope. Events sort ascending by
+`(timestamp, source_rank, event_key)`; missing timestamps sort last.
+
+### Filter authority, and refusing what cannot be answered
+
+A filter dimension is only meaningful for a source whose records carry it.
+Each source declares its own support in `_SOURCE_FILTER_SUPPORT` and reports it
+per response as `supported_filters` / `unsupported_filters`:
+
+| Source | issue | pr | session |
+|---|---|---|---|
+| `control_plane` | yes | yes | **no** — the `events` table is `(event_id, work_item_id, event_type, message, created_at)` and records no session |
+| `gitea_handoff` | yes | yes | yes — a CTH comment declares its own `Session:` field |
+
+`session_id` is read only from that declared CTH field. It is never inferred
+from a work item, an actor, or message text, and a value that is
+redaction-altering or bare-secret-shaped is dropped rather than emitted.
+
+When **no source that ran** can carry a requested dimension, the request is
+refused rather than answered: the response is `422` with `ok:false` and a
+structured `error` naming `unsupported_filters` and the per-source reason. A
+`200` with zero events would tell an operator that no such activity exists,
+which is a stronger — and false — claim than "this cannot be answered here".
+A source that *can* answer the dimension and simply matched nothing still
+returns `200` with `ok:true` and an empty page.
+
+### Redaction
+
+Every free-text field (event messages, decision/proof text, roles, actors) is
+passed through the console redaction policy (`webui.console_redaction`, backed
+by `gitea_audit.redact`) before it leaves the module, failing closed to the
+placeholder. No unredacted tool arguments or secrets are ever emitted, and a
+generation error never drops raw data to a caller or a log.
+
+Redaction also runs *before* any structured value is derived from free text.
+`evidence_refs` are extracted from already-redacted proof/decision text, and a
+commit reference is recognised only where the text declares one (`commit`,
+`head`, `base`, `sha`, …). An undeclared 40-character hex run has the exact
+shape of a Gitea access token, so it is never lifted out of prose into a
+structured field. Every reference is then independently revalidated against an
+allowed shape and a second redaction pass immediately before serialization;
+anything unproven is dropped and the event is flagged `sensitive`.
+
+### Tests
+
+```bash
+pytest tests/test_webui_timeline.py -q
+```
+
 ## Tests
 
 ```bash

gitea_mcp_server.py

@@ -11242,127 +11242,163 @@ def gitea_reconcile_merged_cleanups(
     if dry_run:
         report["dry_run"] = True
         report["executed"] = False
+        # #851: surface planned lifecycle order so dry-run matches execute.
+        report["planned_execution_orders"] = {
+            str(entry.get("pr_number")): entry.get("planned_execution_order") or []
+            for entry in (report.get("entries") or [])
+        }
         return {"success": True, "performed": False, **report}
 
     verify_preflight_purity(
         remote, task="reconcile_merged_cleanups", org=org, repo=repo
     )
     actions: list[dict] = []
+    project_root = _canonical_local_git_root()
+
+    def _ownership_records_for_branch(
+        head_branch: str, pr_num_int: int | None
+    ) -> list[dict]:
+        ownership_bundle = _collect_branch_ownership_records(
+            remote=remote,
+            host=h,
+            org=o,
+            repo=r,
+            branch=head_branch,
+            pr_number=pr_num_int,
+            project_root=project_root,
+            auth=auth,
+            base_api=base,
+        )
+        ownership_records = list(ownership_bundle.get("records") or [])
+        if ownership_bundle.get("inventory_error"):
+            ownership_records.append(
+                {
+                    "category": (
+                        branch_cleanup_guard.OWNERSHIP_CATEGORY_INVENTORY_ERROR
+                    ),
+                    "status": "unknown",
+                    "remote": remote,
+                    "host": h,
+                    "org": o,
+                    "repo": r,
+                    "branch": head_branch,
+                    "reclaim_allowed": False,
+                    "role": "inventory",
+                }
+            )
+        return ownership_records
+
+    def _attempt_owned_remote_delete(
+        *,
+        head_branch: str,
+        pr_num_int: int | None,
+        after_worktree_removal: bool = False,
+    ) -> dict:
+        """Fail-closed remote delete with live ownership reassessment (#851)."""
+        import urllib.parse
+
+        ownership_records = _ownership_records_for_branch(head_branch, pr_num_int)
+        ownership = branch_cleanup_guard.assess_active_branch_ownership(
+            remote=remote,
+            org=o,
+            repo=r,
+            branch=head_branch,
+            host=h,
+            records=ownership_records,
+        )
+        if ownership.get("block"):
+            return {
+                "action": "delete_remote_branch",
+                "branch": head_branch,
+                "success": False,
+                "performed": False,
+                "delete_acknowledged": False,
+                "verified_absent": False,
+                "blocker_kind": "active_branch_ownership",
+                "reasons": ownership.get("reasons") or [],
+                "blocking_categories": ownership.get("blocking_categories") or [],
+                "after_worktree_removal": after_worktree_removal,
+                "ownership_reassessed": after_worktree_removal,
+            }
+
+        encoded = urllib.parse.quote(head_branch, safe="")
+        url = f"{base}/branches/{encoded}"
+        with _audited(
+            "delete_branch",
+            host=h,
+            remote=remote,
+            org=o,
+            repo=r,
+            target_branch=head_branch,
+            request_metadata={
+                "branch": head_branch,
+                "source": "reconcile_merged_cleanups",
+                "ownership_checked": True,
+                "after_worktree_removal": after_worktree_removal,
+            },
+        ):
+            api_request("DELETE", url, auth)
+        readback = _probe_remote_branch(h, o, r, auth, head_branch)
+        readback_assessment = branch_cleanup_guard.assess_post_delete_readback(
+            readback
+        )
+        verified = bool(readback_assessment.get("verified_absent"))
+        return {
+            "action": "delete_remote_branch",
+            "branch": head_branch,
+            "success": bool(readback_assessment.get("ok")),
+            "performed": True,
+            "delete_acknowledged": True,
+            "verified_absent": verified,
+            "readback": readback_assessment.get("readback"),
+            "reasons": readback_assessment.get("reasons") or [],
+            "after_worktree_removal": after_worktree_removal,
+            "ownership_reassessed": after_worktree_removal,
+        }
+
     for entry in report.get("entries") or []:
         head_branch = entry.get("head_branch") or ""
         remote_assessment = entry.get("remote_branch") or {}
         local_assessment = entry.get("local_worktree") or {}
+        pr_num = entry.get("pr_number")
+        try:
+            pr_num_int = int(pr_num) if pr_num is not None else None
+        except (TypeError, ValueError):
+            pr_num_int = None
 
-        if remote_assessment.get("safe_to_delete_remote"):
-            import urllib.parse
-
-            pr_num = entry.get("pr_number")
-            try:
-                pr_num_int = int(pr_num) if pr_num is not None else None
-            except (TypeError, ValueError):
-                pr_num_int = None
-            ownership_bundle = _collect_branch_ownership_records(
-                remote=remote,
-                host=h,
-                org=o,
-                repo=r,
-                branch=head_branch,
-                pr_number=pr_num_int,
-                project_root=_canonical_local_git_root(),
-                auth=auth,
-                base_api=base,
-            )
-            ownership_records = list(ownership_bundle.get("records") or [])
-            if ownership_bundle.get("inventory_error"):
-                ownership_records.append(
-                    {
-                        "category": (
-                            branch_cleanup_guard.OWNERSHIP_CATEGORY_INVENTORY_ERROR
-                        ),
-                        "status": "unknown",
-                        "remote": remote,
-                        "host": h,
-                        "org": o,
-                        "repo": r,
-                        "branch": head_branch,
-                        "reclaim_allowed": False,
-                        "role": "inventory",
-                    }
-                )
-            ownership = branch_cleanup_guard.assess_active_branch_ownership(
-                remote=remote,
-                org=o,
-                repo=r,
-                branch=head_branch,
-                host=h,
-                records=ownership_records,
-            )
-            if ownership.get("block"):
-                actions.append(
-                    {
-                        "action": "delete_remote_branch",
-                        "branch": head_branch,
-                        "success": False,
-                        "performed": False,
-                        "delete_acknowledged": False,
-                        "verified_absent": False,
-                        "blocker_kind": "active_branch_ownership",
-                        "reasons": ownership.get("reasons") or [],
-                        "blocking_categories": ownership.get(
-                            "blocking_categories"
-                        )
-                        or [],
-                    }
-                )
-                continue
-
-            encoded = urllib.parse.quote(head_branch, safe="")
-            url = f"{base}/branches/{encoded}"
-            with _audited(
-                "delete_branch",
-                host=h,
-                remote=remote,
-                org=o,
-                repo=r,
-                target_branch=head_branch,
-                request_metadata={
-                    "branch": head_branch,
-                    "source": "reconcile_merged_cleanups",
-                    "ownership_checked": True,
-                },
-            ):
-                api_request("DELETE", url, auth)
-            readback = _probe_remote_branch(h, o, r, auth, head_branch)
-            readback_assessment = branch_cleanup_guard.assess_post_delete_readback(
-                readback
-            )
-            verified = bool(readback_assessment.get("verified_absent"))
-            actions.append(
-                {
-                    "action": "delete_remote_branch",
-                    "branch": head_branch,
-                    "success": bool(readback_assessment.get("ok")),
-                    "performed": True,
-                    "delete_acknowledged": True,
-                    "verified_absent": verified,
-                    "readback": readback_assessment.get("readback"),
-                    "reasons": readback_assessment.get("reasons") or [],
-                }
-            )
-
+        # #851 lifecycle: when the target worktree is independently safe, remove
+        # it first so worktree_binding ownership does not permanently strand
+        # both the worktree and the remote branch. Never skip worktree removal
+        # merely because remote delete would be blocked by that binding.
+        # Ownership protection for remote delete remains fail-closed below.
+        worktree_removed = False
         if local_assessment.get("safe_to_remove_worktree"):
             result = merged_cleanup_reconcile.remove_local_worktree(
-                _canonical_local_git_root(),
+                project_root,
                 head_branch,
                 worktree_path=local_assessment.get("worktree_path"),
             )
             actions.append({"action": "remove_local_worktree", **result})
+            # Idempotent resume: absent worktree is already gone.
+            msg = (result.get("message") or "").lower()
+            worktree_removed = bool(result.get("success")) or (
+                "not found" in msg
+            )
+
+        if remote_assessment.get("safe_to_delete_remote"):
+            actions.append(
+                _attempt_owned_remote_delete(
+                    head_branch=head_branch,
+                    pr_num_int=pr_num_int,
+                    after_worktree_removal=worktree_removed,
+                )
+            )
 
     for scratch in report.get("reviewer_scratch_entries") or []:
         if not scratch.get("safe_to_remove_worktree"):
             continue
         result = merged_cleanup_reconcile.remove_reviewer_scratch_worktree(
-            _canonical_local_git_root(), scratch.get("worktree_path") or ""
+            project_root, scratch.get("worktree_path") or ""
         )
         actions.append({"action": "remove_reviewer_scratch_worktree", **result})
 
@@ -19912,6 +19948,7 @@ def _allocator_candidates_from_gitea(
                         state="open",
                         labels=tuple(labels),
                         title=title,
+                        body=body,
                         priority=20 if "status:ready" in labels else 1,
                         blocked=blocked,
                         dependency_unmet=dep_unmet,
@@ -21148,10 +21185,21 @@ def gitea_adopt_workflow_lease(
     remote: str = "dadeschools",
     host: str | None = None,
 ) -> dict:
-    """Adopt a control-plane lease through the sanctioned path (#601).
+    """Adopt a control-plane lease through the sanctioned path (#601 / #843).
 
-    Same-owner resume refreshes provenance. Foreign active leases are refused.
-    Expired leases may be reclaimed; provenance records adopted_from/by.
+    Same-owner resume refreshes provenance. Foreign active leases are refused
+    unless the lease is a pending controller cross-role handoff and the caller
+    holds the required role (independent consume without sharing the
+    controller session). Expired leases may be reclaimed; provenance records
+    adopted_from/by. Terminal (abandoned/released) leases cannot be adopted.
+
+    #843 F1: the adopter role is derived authoritatively from the active
+    authenticated profile — never from caller input. A supplied ``role`` that
+    does not exactly match the profile-derived role is rejected (no silent
+    accept or reinterpretation), and handoff provenance ``required_profile`` /
+    ``required_namespace`` restrictions are validated against the same
+    authoritative caller context. Caller-supplied role/profile/namespace can
+    never grant authority.
     """
     read_block = _profile_operation_gate("gitea.read")
     if read_block:
@@ -21160,25 +21208,64 @@ def gitea_adopt_workflow_lease(
             "reasons": read_block,
             "permission_report": _permission_block_report("gitea.read"),
         }
+    profile = get_profile()
+    profile_name = (profile.get("profile_name") or "").strip() or "session"
+    active_role = (_profile_role_kind(profile) or "").strip().lower()
+    if not active_role:
+        return {
+            "success": False,
+            "outcome": "blocked",
+            "mutation_performed": False,
+            "reasons": [
+                "active profile role could not be derived authoritatively; "
+                "refusing lease adoption (fail closed, #843)"
+            ],
+            "lease_id": lease_id,
+            "authoritative_source": "control_plane_db",
+            "file_lock_only": False,
+            "comment_lease_only": False,
+        }
+    if role is not None and str(role).strip():
+        supplied_role = str(role).strip().lower()
+        if supplied_role != active_role:
+            return {
+                "success": False,
+                "outcome": "blocked",
+                "mutation_performed": False,
+                "profile_role_kind": active_role,
+                "supplied_role": supplied_role,
+                "reasons": [
+                    f"caller-supplied role '{supplied_role}' does not match "
+                    f"the authenticated profile-derived role '{active_role}'; "
+                    "caller-supplied role/profile/namespace can never grant "
+                    "authority (fail closed, #843)"
+                ],
+                "lease_id": lease_id,
+                "authoritative_source": "control_plane_db",
+                "file_lock_only": False,
+                "comment_lease_only": False,
+            }
     db, errs = _control_plane_db_or_error()
     if db is None:
         return {"success": False, "reasons": errs}
-    profile = get_profile()
-    profile_name = (profile.get("profile_name") or "").strip() or "session"
-    active_role = _profile_role_kind(profile) or "author"
     sid = (session_id or "").strip() or (
         f"{profile_name}-{os.getpid()}-{uuid.uuid4().hex[:8]}"
     )
+    adopter_namespace = allocator_service.DEFAULT_ROLE_NAMESPACES.get(
+        active_role, f"gitea-{active_role}"
+    )
     try:
         return lease_lifecycle.adopt_lease(
             db,
             lease_id=lease_id,
             adopter_session_id=sid,
-            role=(role or active_role).strip() or "author",
+            role=active_role,
             worktree_path=worktree_path,
             expected_head_sha=expected_head_sha,
             owner_pid=os.getpid(),
             operator_authorized=bool(operator_authorized),
+            adopter_profile_name=profile_name,
+            adopter_namespace=adopter_namespace,
         )
     except (lease_lifecycle.LeaseLifecycleError, control_plane_db.ControlPlaneError) as exc:
         return {

lease_lifecycle.py

@@ -39,6 +39,7 @@ SAFE_RELEASE_OWNED = "release_owned"
 SAFE_STALE_PROMPT = "stale_prompt_lease"
 SAFE_UNKNOWN = "inspect_only"
 SAFE_NO_AUTHORITY = "file_or_comment_not_authoritative"
+SAFE_CONSUME_CROSS_ROLE = "consume_cross_role_handoff"
 
 LEASE_STATUS_ACTIVE = "active"
 LEASE_STATUS_RELEASED = "released"
@@ -250,6 +251,23 @@ def decide_safe_next_action(
                 "same_owner": True,
                 "also_allowed": [SAFE_ABANDON_ALLOWED, SAFE_RELEASE_OWNED],
             }
+        handoff = is_pending_cross_role_handoff({"lease": lease})
+        if handoff:
+            return {
+                "safe_next_action": SAFE_CONSUME_CROSS_ROLE,
+                "reasons": [
+                    f"controller allocation pending handoff (freshness={status}); "
+                    "required-role worker may consume without abandon/reassign; "
+                    f"required_role={handoff['required_role']}"
+                ],
+                "block": False,
+                "same_owner": False,
+                "owner_session_id": owner,
+                "required_role": handoff["required_role"],
+                "cross_role_handoff": True,
+                "handoff_status": "pending",
+                "also_allowed": [SAFE_ABANDON_ALLOWED],
+            }
         return {
             "safe_next_action": SAFE_ABANDON_ALLOWED,
             "reasons": [
@@ -272,6 +290,24 @@ def decide_safe_next_action(
         }
 
     if not same_owner and status == "active":
+        # #843: pending cross-role handoff is consumable by required role
+        handoff = is_pending_cross_role_handoff({"lease": lease})
+        if handoff:
+            return {
+                "safe_next_action": SAFE_CONSUME_CROSS_ROLE,
+                "reasons": [
+                    "controller cross-role allocation pending handoff; "
+                    f"required_role={handoff['required_role']}; "
+                    "consume via gitea_adopt_workflow_lease without "
+                    "abandonment or sharing the controller session"
+                ],
+                "block": False,
+                "same_owner": False,
+                "owner_session_id": owner,
+                "required_role": handoff["required_role"],
+                "cross_role_handoff": True,
+                "handoff_status": "pending",
+            }
         return {
             "safe_next_action": SAFE_WAIT_FOREIGN,
             "reasons": [
@@ -440,6 +476,84 @@ def list_active_leases(
     }
 
 
+
+def parse_lease_provenance(lease_or_state: Mapping[str, Any] | None) -> dict[str, Any]:
+    """Return durable lease provenance dict (empty when absent/unparseable)."""
+    if not lease_or_state:
+        return {}
+    if "provenance" in lease_or_state and isinstance(lease_or_state.get("provenance"), dict):
+        return dict(lease_or_state["provenance"])
+    raw = None
+    if "provenance_json" in lease_or_state:
+        raw = lease_or_state.get("provenance_json")
+    elif "lease" in lease_or_state and isinstance(lease_or_state.get("lease"), Mapping):
+        raw = lease_or_state["lease"].get("provenance_json")
+    if not raw:
+        return {}
+    if isinstance(raw, dict):
+        return dict(raw)
+    try:
+        loaded = json.loads(raw)
+    except (TypeError, json.JSONDecodeError):
+        return {}
+    return dict(loaded) if isinstance(loaded, dict) else {}
+
+
+def is_pending_cross_role_handoff(
+    state: Mapping[str, Any] | None,
+) -> dict[str, Any] | None:
+    """Return handoff evidence when a controller allocation awaits consume (#843).
+
+    A pending handoff is identified by durable provenance written at
+    cross-role apply time — not by title heuristics or session-id guessing.
+    """
+    if not state:
+        return None
+    lease = state.get("lease") if isinstance(state.get("lease"), Mapping) else state
+    if not isinstance(lease, Mapping):
+        return None
+    status = str(lease.get("status") or "").strip().lower()
+    if status in (LEASE_STATUS_ABANDONED, LEASE_STATUS_RELEASED, LEASE_STATUS_EXPIRED):
+        return None
+    prov = parse_lease_provenance(state)
+    if not prov and isinstance(lease, Mapping):
+        prov = parse_lease_provenance(lease)
+    if not prov.get("cross_role_handoff"):
+        return None
+    handoff_status = str(prov.get("handoff_status") or "pending").strip().lower()
+    if handoff_status != "pending":
+        return None
+    adopted_by = (
+        lease.get("adopted_by_session_id")
+        or prov.get("adopted_by_session_id")
+        or ""
+    )
+    if str(adopted_by).strip():
+        return None
+    required_role = str(
+        prov.get("required_role") or lease.get("role") or ""
+    ).strip().lower()
+    if not required_role:
+        return None
+    return {
+        "cross_role_handoff": True,
+        "handoff_status": "pending",
+        "required_role": required_role,
+        "allocating_session_id": str(
+            prov.get("allocating_session_id") or lease.get("session_id") or ""
+        ),
+        "allocating_role": str(prov.get("allocating_role") or "controller"),
+        "lease_id": str(lease.get("lease_id") or ""),
+        "assignment_id": (
+            str(state["assignment"]["assignment_id"])
+            if isinstance(state.get("assignment"), Mapping)
+            and state["assignment"].get("assignment_id")
+            else None
+        ),
+        "provenance": prov,
+    }
+
+
 def adopt_lease(
     db: cpd.ControlPlaneDB,
     *,
@@ -450,8 +564,17 @@ def adopt_lease(
     expected_head_sha: str | None = None,
     owner_pid: int | None = None,
     operator_authorized: bool = False,
+    adopter_profile_name: str | None = None,
+    adopter_namespace: str | None = None,
 ) -> dict[str, Any]:
-    """Sanctioned adopt path with provenance; never silent foreign steal."""
+    """Sanctioned adopt path with provenance; never silent foreign steal.
+
+    #843 F1: for a pending cross-role handoff, ``role`` must be the
+    authoritative profile-derived role supplied by the MCP boundary — never
+    caller-asserted authority. When the handoff provenance declares
+    ``required_profile`` / ``required_namespace`` and the caller context is
+    provided, both are validated exactly; a mismatch fails closed.
+    """
     state = db.get_lease_workflow_state(lease_id)
     if not state:
         raise LeaseLifecycleError(
@@ -463,11 +586,8 @@ def adopt_lease(
     owner = str(lease.get("session_id") or "")
     same_owner = owner == str(adopter_session_id)
 
-    if freshness["freshness"] == "active" and not same_owner:
-        raise LeaseLifecycleError(
-            f"refusing to steal active foreign lease {lease_id} owned by "
-            f"{owner} (fail closed)"
-        )
+    handoff = is_pending_cross_role_handoff(state)
+    adopter_role = (role or "").strip().lower()
 
     if freshness["freshness"] in ("abandoned", "released"):
         raise LeaseLifecycleError(
@@ -475,13 +595,64 @@ def adopt_lease(
             "(fail closed)"
         )
 
-    # Expired or stale: require abandon-style safety before ownership transfer
-    # when not same owner; same owner may reclaim.
-    if not same_owner and freshness["freshness"] in (
+    if handoff and not same_owner:
+        # Terminal statuses already rejected above. Freshness may be
+        # active OR stale_dead_process (controller exited) — both are
+        # consumable without abandonment when handoff is still pending.
+        if freshness["freshness"] not in (
+            "active",
+            "stale_dead_process",
+            "stale_missing_worktree",
+        ):
+            raise LeaseLifecycleError(
+                f"lease {lease_id} freshness={freshness['freshness']}; "
+                "terminal or non-active allocation cannot be handoff-consumed "
+                "(fail closed)"
+            )
+        required = handoff["required_role"]
+        if adopter_role != required:
+            raise LeaseLifecycleError(
+                f"wrong role for cross-role handoff consume of {lease_id}: "
+                f"required={required} adopter={adopter_role or 'none'} "
+                "(fail closed)"
+            )
+        # #843 F1: provenance profile/namespace restrictions are validated
+        # against the authoritative caller context when declared. Caller
+        # input can never widen authority; a mismatch fails closed.
+        handoff_prov = handoff.get("provenance") or {}
+        required_profile = str(
+            handoff_prov.get("required_profile") or ""
+        ).strip()
+        if required_profile and adopter_profile_name is not None:
+            if str(adopter_profile_name).strip() != required_profile:
+                raise LeaseLifecycleError(
+                    f"wrong profile for cross-role handoff consume of "
+                    f"{lease_id}: required_profile={required_profile} "
+                    f"adopter_profile={adopter_profile_name} (fail closed)"
+                )
+        required_namespace = str(
+            handoff_prov.get("required_namespace") or ""
+        ).strip()
+        if required_namespace and adopter_namespace is not None:
+            if str(adopter_namespace).strip() != required_namespace:
+                raise LeaseLifecycleError(
+                    f"wrong namespace for cross-role handoff consume of "
+                    f"{lease_id}: required_namespace={required_namespace} "
+                    f"adopter_namespace={adopter_namespace} (fail closed)"
+                )
+        reason = "cross-role-handoff-consume"
+    elif freshness["freshness"] == "active" and not same_owner:
+        raise LeaseLifecycleError(
+            f"refusing to steal active foreign lease {lease_id} owned by "
+            f"{owner} (fail closed)"
+        )
+    elif not same_owner and freshness["freshness"] in (
         "expired",
         "stale_dead_process",
         "stale_missing_worktree",
     ):
+        # Expired or stale (non-handoff): require abandon-style safety before
+        # ownership transfer when not same owner; same owner may reclaim.
         if not operator_authorized and freshness["freshness"] == "expired":
             # Deterministic reclaim of expired foreign lease is allowed
             # without operator flag (sanctioned expire reclaim).
@@ -492,6 +663,9 @@ def adopt_lease(
                 f"lease {lease_id} freshness={freshness['freshness']}; "
                 "use abandon with proof before foreign adopt (fail closed)"
             )
+        reason = "sanctioned-reclaim-adopt"
+    else:
+        reason = "owner-resume-adopt" if same_owner else "sanctioned-reclaim-adopt"
 
     provenance = build_adopt_provenance(
         adopted_from_session_id=owner,
@@ -504,10 +678,14 @@ def adopt_lease(
         worktree_path=worktree_path,
         expected_head_sha=expected_head_sha or lease.get("expected_head_sha"),
         prior_lease_id=lease_id,
-        reason=(
-            "owner-resume-adopt" if same_owner else "sanctioned-reclaim-adopt"
-        ),
+        reason=reason,
     )
+    if handoff and not same_owner:
+        provenance["cross_role_handoff"] = True
+        provenance["handoff_status"] = "adopted"
+        provenance["required_role"] = handoff["required_role"]
+        provenance["allocating_session_id"] = handoff["allocating_session_id"]
+        provenance["allocating_role"] = handoff["allocating_role"]
 
     result = db.adopt_lease(
         lease_id=lease_id,
@@ -518,7 +696,7 @@ def adopt_lease(
         owner_pid=owner_pid if owner_pid is not None else os.getpid(),
         provenance=provenance,
     )
-    return {
+    out = {
         "success": True,
         "outcome": result.get("outcome"),
         "same_owner": same_owner,
@@ -531,6 +709,24 @@ def adopt_lease(
         "comment_lease_only": False,
         "reasons": result.get("reasons") or [],
     }
+    if handoff and not same_owner:
+        out["cross_role_handoff"] = True
+        out["handoff_status"] = "adopted"
+        out["required_role"] = handoff["required_role"]
+        out["adopted_by_session_id"] = adopter_session_id
+        out["adopted_from_session_id"] = owner
+        lease_row = result.get("lease") or {}
+        if isinstance(lease_row, Mapping):
+            out["read_after_write"] = {
+                "lease_id": lease_row.get("lease_id"),
+                "session_id": lease_row.get("session_id"),
+                "role": lease_row.get("role"),
+                "status": lease_row.get("status"),
+                "adopted_by_session_id": lease_row.get("adopted_by_session_id"),
+                "adopted_from_session_id": lease_row.get("adopted_from_session_id"),
+                "phase": lease_row.get("phase"),
+            }
+    return out
 
 
 def release_lease(

merged_cleanup_reconcile.py

@@ -566,6 +566,10 @@ def build_pr_cleanup_entry(
         worktree_state=worktree_state,
         active_lock=active_lock,
     )
+    planned = plan_cleanup_execution_order(
+        remote_assessment=remote,
+        local_assessment=local,
+    )
     return {
         "pr_number": pr_number,
         "issue_number": issue_number,
@@ -576,9 +580,63 @@ def build_pr_cleanup_entry(
         "merged": merged,
         "remote_branch": remote,
         "local_worktree": local,
+        # #851: dry-run and execute share the same lifecycle order description.
+        "planned_execution_order": planned,
     }
 
 
+def plan_cleanup_execution_order(
+    *,
+    remote_assessment: dict[str, Any] | None,
+    local_assessment: dict[str, Any] | None,
+) -> list[dict[str, Any]]:
+    """Describe independent worktree-then-reassess-then-remote cleanup order (#851).
+
+    Remote ownership protection remains fail-closed at execute time. A worktree
+    that is independently safe to remove is never skipped merely because remote
+    deletion may be blocked by that same ``worktree_binding``.
+    """
+    remote = remote_assessment or {}
+    local = local_assessment or {}
+    steps: list[dict[str, Any]] = []
+    worktree_safe = bool(local.get("safe_to_remove_worktree"))
+    remote_safe = bool(remote.get("safe_to_delete_remote"))
+
+    if worktree_safe:
+        steps.append(
+            {
+                "action": "remove_local_worktree",
+                "reason": "independently_safe_to_remove",
+                "phase": 1,
+            }
+        )
+    if remote_safe:
+        if worktree_safe:
+            steps.append(
+                {
+                    "action": "reassess_branch_ownership",
+                    "reason": "after_worktree_removal_clear_worktree_binding",
+                    "phase": 2,
+                }
+            )
+            steps.append(
+                {
+                    "action": "delete_remote_branch",
+                    "reason": "only_if_independently_safe_after_reassessment",
+                    "phase": 3,
+                }
+            )
+        else:
+            steps.append(
+                {
+                    "action": "delete_remote_branch",
+                    "reason": "safe_to_delete_and_no_independent_worktree_removal",
+                    "phase": 1,
+                }
+            )
+    return steps
+
+
 def build_reconciliation_report(
     *,
     project_root: str,

tests/test_allocator_epic_container_exclusion.py

@@ -0,0 +1,243 @@
+"""Allocator epic / child-only container pre-rank exclusion (#844).
+
+Covers:
+* Issue #631-shaped child-only epic is excluded before ranking.
+* Implementable child issues remain eligible and can be selected.
+* Ordinary issues that merely mention "epic" in title/body are not excluded.
+* Excluded containers never receive assignments or workflow leases.
+* Structured skip reason ``epic_or_child_only_container`` is reported.
+"""
+
+from __future__ import annotations
+
+import os
+import tempfile
+import unittest
+
+from allocator_service import (
+    OUTCOME_ASSIGNED,
+    OUTCOME_PREVIEW,
+    SKIP_EPIC_OR_CHILD_ONLY_CONTAINER,
+    WorkCandidate,
+    allocate_next_work,
+    classify_epic_or_child_only_container,
+)
+from control_plane_db import ControlPlaneDB
+
+REMOTE = "prgs"
+ORG = "Scaled-Tech-Consulting"
+REPO = "Gitea-Tools"
+
+# Minimal body mirroring issue #631 authoritative scope language.
+_EPIC_631_BODY = """
+## Scope (umbrella)
+
+This epic owns the **product roadmap and linkage** for the Web Console.
+Implementation is delivered via child issues only.
+
+## Explicit non-goals
+
+* Do not implement product features in this epic issue itself.
+* No product feature implementation is claimed complete solely on this epic.
+"""
+
+_CHILD_BODY = """
+## Problem
+
+Operators need a workflow-event timeline model for Phase 1.
+
+## Acceptance criteria
+
+- [ ] Timeline model API exists
+"""
+
+
+def _issue(
+    number: int,
+    *,
+    title: str = "",
+    body: str = "",
+    labels: tuple[str, ...] = ("status:ready", "type:feature"),
+    priority: int = 20,
+) -> WorkCandidate:
+    return WorkCandidate(
+        kind="issue",
+        number=number,
+        state="open",
+        labels=labels,
+        title=title or f"issue {number}",
+        body=body,
+        priority=priority,
+    )
+
+
+class ClassifyEpicContainerTest(unittest.TestCase):
+    def test_631_shaped_body_and_title_is_container(self) -> None:
+        c = _issue(
+            631,
+            title="Epic: MCP Control Plane Web Console",
+            body=_EPIC_631_BODY,
+        )
+        is_c, detail = classify_epic_or_child_only_container(c)
+        self.assertTrue(is_c)
+        self.assertIsNotNone(detail)
+        self.assertIn("body_marker", detail or "")
+
+    def test_body_markers_without_epic_title(self) -> None:
+        c = _issue(
+            900,
+            title="Control plane roadmap tracker",
+            body="Implementation is delivered via child issues only.",
+        )
+        is_c, _ = classify_epic_or_child_only_container(c)
+        self.assertTrue(is_c)
+
+    def test_epic_label_alone_is_container(self) -> None:
+        c = _issue(
+            901,
+            title="Roadmap linkage",
+            body="Track children.",
+            labels=("status:ready", "type:epic"),
+        )
+        is_c, detail = classify_epic_or_child_only_container(c)
+        self.assertTrue(is_c)
+        self.assertIn("type:epic", detail or "")
+
+    def test_title_epic_prefix_alone_not_container(self) -> None:
+        """Title-only 'Epic:' without body scope evidence stays eligible (#844)."""
+        c = _issue(
+            902,
+            title="Epic: something mentioned only in title",
+            body="Implement a concrete fix for the allocator skip list.",
+        )
+        is_c, detail = classify_epic_or_child_only_container(c)
+        self.assertFalse(is_c)
+        self.assertIsNone(detail)
+
+    def test_incidental_epic_word_not_container(self) -> None:
+        c = _issue(
+            903,
+            title="Document epic handoff conventions",
+            body=(
+                "Update the docs so implementable issues that mention an epic "
+                "remain independently executable."
+            ),
+        )
+        is_c, _ = classify_epic_or_child_only_container(c)
+        self.assertFalse(is_c)
+
+    def test_prs_never_classified(self) -> None:
+        pr = WorkCandidate(
+            kind="pr",
+            number=10,
+            state="open",
+            title="Epic: fake",
+            body="Implementation is delivered via child issues only.",
+            head_sha="a" * 40,
+            priority=5,
+        )
+        is_c, _ = classify_epic_or_child_only_container(pr)
+        self.assertFalse(is_c)
+
+
+class AllocateEpicContainerExclusionTest(unittest.TestCase):
+    def setUp(self) -> None:
+        self._tmp = tempfile.TemporaryDirectory()
+        self.addCleanup(self._tmp.cleanup)
+        self.db = ControlPlaneDB(os.path.join(self._tmp.name, "cp.sqlite3"))
+
+    def _alloc(self, candidates, **kwargs):
+        defaults = dict(
+            session_id="sess-844",
+            role="author",
+            remote=REMOTE,
+            org=ORG,
+            repo=REPO,
+            profile_name="prgs-author",
+            username="jcwalker3",
+            claims={},
+            apply=False,
+        )
+        defaults.update(kwargs)
+        return allocate_next_work(self.db, candidates=candidates, **defaults)
+
+    def test_631_shaped_epic_excluded_child_selected(self) -> None:
+        epic = _issue(
+            631,
+            title="Epic: MCP Control Plane Web Console",
+            body=_EPIC_631_BODY,
+        )
+        child = _issue(
+            637,
+            title="Web Console: Workflow-event timeline model (Phase 1)",
+            body=_CHILD_BODY,
+        )
+        res = self._alloc([epic, child], apply=False)
+        self.assertTrue(res["success"], res)
+        self.assertEqual(res["outcome"], OUTCOME_PREVIEW)
+        self.assertEqual(res["selected"]["number"], 637)
+        skipped = {s["number"]: s for s in res["skipped"]}
+        self.assertIn(631, skipped)
+        self.assertEqual(
+            skipped[631]["reason_code"], SKIP_EPIC_OR_CHILD_ONLY_CONTAINER
+        )
+        self.assertIn(SKIP_EPIC_OR_CHILD_ONLY_CONTAINER, skipped[631]["reason"])
+
+    def test_container_cannot_receive_assignment_or_lease(self) -> None:
+        epic = _issue(
+            631,
+            title="Epic: MCP Control Plane Web Console",
+            body=_EPIC_631_BODY,
+        )
+        res = self._alloc([epic], apply=True)
+        self.assertTrue(res["success"], res)
+        # Only container present → no safe work; never assigned_work.
+        self.assertNotEqual(res["outcome"], OUTCOME_ASSIGNED)
+        self.assertIsNone(res.get("assignment"))
+        self.assertIsNone(res.get("selected"))
+        skipped = {s["number"]: s for s in res["skipped"]}
+        self.assertEqual(
+            skipped[631]["reason_code"], SKIP_EPIC_OR_CHILD_ONLY_CONTAINER
+        )
+        # No lease row for the epic.
+        leases = self.db.list_active_leases(
+            remote=REMOTE, org=ORG, repo=REPO
+        ) if hasattr(self.db, "list_active_leases") else []
+        # Prefer generic inventory if available.
+        if not leases and hasattr(self.db, "list_leases"):
+            leases = self.db.list_leases(remote=REMOTE, org=ORG, repo=REPO)
+        for lease in leases or []:
+            work_number = lease.get("work_number") if isinstance(lease, dict) else None
+            self.assertNotEqual(work_number, 631)
+
+    def test_incidental_epic_title_remains_eligible(self) -> None:
+        ordinary = _issue(
+            700,
+            title="Document epic handoff conventions",
+            body="Write runbook text about epic vs child issues.",
+        )
+        res = self._alloc([ordinary], apply=False)
+        self.assertTrue(res["success"], res)
+        self.assertEqual(res["selected"]["number"], 700)
+        self.assertEqual(res["skipped"], [])
+
+    def test_apply_selects_child_not_epic(self) -> None:
+        epic = _issue(
+            631,
+            title="Epic: MCP Control Plane Web Console",
+            body=_EPIC_631_BODY,
+        )
+        child = _issue(
+            637,
+            title="Web Console: Workflow-event timeline model (Phase 1)",
+            body=_CHILD_BODY,
+        )
+        res = self._alloc([epic, child], apply=True)
+        self.assertTrue(res["success"], res)
+        self.assertEqual(res["outcome"], OUTCOME_ASSIGNED)
+        self.assertEqual(res["selected"]["number"], 637)
+        self.assertEqual(res["assignment"]["work_number"], 637)
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_branch_cleanup_guard.py

@@ -1266,6 +1266,378 @@ class TestSecondRemediationIntegration(unittest.TestCase):
         self.assertIn("delete_acknowledged", delete_actions[0])
         self.assertTrue(delete_actions[0].get("verified_absent"))
 
+    def test_issue_851_worktree_removed_when_remote_blocked_only_by_worktree_binding(self):
+        """#851: remote blocked by worktree_binding must not skip safe worktree removal.
+
+        Lifecycle: remove clean owned worktree → reassess ownership → delete
+        remote only if independently safe. Unrelated entries stay untouched.
+        """
+        from mcp_server import gitea_reconcile_merged_cleanups
+
+        target_branch = "fix/issue-844-exclude-epic-containers"
+        foreign_branch = "fix/issue-999-unrelated-active"
+        worktree_path = "/tmp/branches/fix-issue-844-exclude-epic-containers"
+        ownership_calls = []
+        remove_calls = []
+        delete_api_calls = []
+
+        def fake_collect(**kwargs):
+            ownership_calls.append(dict(kwargs))
+            # Ownership is reassessed *after* independent worktree removal (#851).
+            # Target worktree is already gone → no worktree_binding remains.
+            # Foreign branch keeps an active author lease → remote delete blocked.
+            if kwargs.get("branch") == foreign_branch:
+                # Match session-bound org/repo + host used by the tool resolve path.
+                return {
+                    "records": [
+                        {
+                            "category": guard.OWNERSHIP_CATEGORY_AUTHOR_LEASE,
+                            "status": "active",
+                            "remote": kwargs.get("remote") or "prgs",
+                            "host": kwargs.get("host") or "gitea.example.com",
+                            "org": kwargs.get("org") or "Scaled-Tech-Consulting",
+                            "repo": kwargs.get("repo") or "Gitea-Tools",
+                            "branch": foreign_branch,
+                            "reclaim_allowed": False,
+                        }
+                    ],
+                    "inventory_error": False,
+                }
+            return {"records": [], "inventory_error": False}
+
+        def fake_remove(project_root, branch, worktree_path=None):
+            remove_calls.append(
+                {"branch": branch, "worktree_path": worktree_path}
+            )
+            return {
+                "success": True,
+                "performed": True,
+                "message": f"removed worktree {worktree_path}",
+                "worktree_path": worktree_path,
+            }
+
+        def fake_probe(h, o, r, auth, br):
+            return guard.classify_branch_readback_http_status(
+                404, not_found_scope=guard.NOT_FOUND_SCOPE_BRANCH
+            )
+
+        def fake_api(method, url, auth, **kwargs):
+            if method == "DELETE":
+                delete_api_calls.append(url)
+            return {}
+
+        report = {
+            "entries": [
+                {
+                    "pr_number": 848,
+                    "head_branch": target_branch,
+                    "remote_branch": {"safe_to_delete_remote": True},
+                    "local_worktree": {
+                        "safe_to_remove_worktree": True,
+                        "worktree_path": worktree_path,
+                    },
+                },
+                {
+                    "pr_number": 999,
+                    "head_branch": foreign_branch,
+                    "remote_branch": {"safe_to_delete_remote": True},
+                    "local_worktree": {
+                        "safe_to_remove_worktree": False,
+                        "worktree_path": None,
+                    },
+                },
+            ],
+            "reviewer_scratch_entries": [],
+        }
+        patch(
+            "mcp_server.get_profile",
+            return_value={
+                "profile_name": "prgs-reconciler",
+                "role": "reconciler",
+                "allowed_operations": [
+                    "gitea.read",
+                    "gitea.branch.delete",
+                    "gitea.pr.close",
+                ],
+                "forbidden_operations": [],
+            },
+        ).start()
+        patch("mcp_server.api_get_all", return_value=[]).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.build_reconciliation_report",
+            return_value=report,
+        ).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.discover_reviewer_scratch_worktrees",
+            return_value=[],
+        ).start()
+        patch(
+            "mcp_server.audit_reconciliation_mode.check_cleanup_execution_allowed",
+            return_value=(True, []),
+        ).start()
+        patch("mcp_server.verify_preflight_purity", return_value=None).start()
+        patch(
+            "mcp_server._collect_branch_ownership_records",
+            side_effect=fake_collect,
+        ).start()
+        patch("mcp_server._probe_remote_branch", side_effect=fake_probe).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.remove_local_worktree",
+            side_effect=fake_remove,
+        ).start()
+        self.mock_api.side_effect = fake_api
+
+        res = gitea_reconcile_merged_cleanups(
+            dry_run=False,
+            execute_confirmed=True,
+            remote="prgs",
+        )
+        self.assertTrue(res.get("performed") or res.get("executed"))
+        actions = res.get("actions") or []
+
+        remove_actions = [
+            a for a in actions if a.get("action") == "remove_local_worktree"
+        ]
+        self.assertEqual(len(remove_actions), 1, actions)
+        self.assertTrue(remove_actions[0].get("success"))
+        self.assertEqual(remove_calls[0]["branch"], target_branch)
+        self.assertEqual(remove_calls[0]["worktree_path"], worktree_path)
+
+        # Target remote delete succeeds after worktree removal + reassessment.
+        target_deletes = [
+            a
+            for a in actions
+            if a.get("action") == "delete_remote_branch"
+            and a.get("branch") == target_branch
+        ]
+        self.assertEqual(len(target_deletes), 1, actions)
+        self.assertTrue(target_deletes[0].get("success"))
+        self.assertTrue(target_deletes[0].get("after_worktree_removal"))
+        self.assertTrue(target_deletes[0].get("ownership_reassessed"))
+        self.assertTrue(target_deletes[0].get("verified_absent"))
+
+        # Foreign branch remains protected (author lease) and is not deleted.
+        foreign_deletes = [
+            a
+            for a in actions
+            if a.get("action") == "delete_remote_branch"
+            and a.get("branch") == foreign_branch
+        ]
+        self.assertEqual(len(foreign_deletes), 1, actions)
+        self.assertFalse(foreign_deletes[0].get("success"))
+        self.assertEqual(
+            foreign_deletes[0].get("blocker_kind"), "active_branch_ownership"
+        )
+        self.assertIn(
+            guard.OWNERSHIP_CATEGORY_AUTHOR_LEASE,
+            foreign_deletes[0].get("blocking_categories") or [],
+        )
+        # Only the target branch should hit the DELETE API.
+        self.assertEqual(len(delete_api_calls), 1)
+
+        # Ownership collected for target (post-removal) and foreign; worktree
+        # removal happened before target remote delete in the action log.
+        target_idx = next(
+            i
+            for i, a in enumerate(actions)
+            if a.get("action") == "remove_local_worktree"
+        )
+        delete_idx = next(
+            i
+            for i, a in enumerate(actions)
+            if a.get("action") == "delete_remote_branch"
+            and a.get("branch") == target_branch
+            and a.get("success")
+        )
+        self.assertLess(target_idx, delete_idx)
+
+    def test_issue_851_dirty_worktree_not_removed_and_remote_stays_protected(self):
+        """#851: dirty/foreign worktrees remain protected; no unsafe cleanup."""
+        from mcp_server import gitea_reconcile_merged_cleanups
+
+        branch = "fix/issue-851-dirty"
+        remove_calls = []
+
+        def fake_collect(**kwargs):
+            return {
+                "records": [
+                    {
+                        "category": guard.OWNERSHIP_CATEGORY_WORKTREE_BINDING,
+                        "status": "active",
+                        "remote": kwargs.get("remote") or "prgs",
+                        "host": kwargs.get("host") or "gitea.example.com",
+                        "org": kwargs.get("org") or "Scaled-Tech-Consulting",
+                        "repo": kwargs.get("repo") or "Gitea-Tools",
+                        "branch": branch,
+                        "reclaim_allowed": False,
+                    }
+                ],
+                "inventory_error": False,
+            }
+
+        report = {
+            "entries": [
+                {
+                    "pr_number": 851,
+                    "head_branch": branch,
+                    "remote_branch": {"safe_to_delete_remote": True},
+                    "local_worktree": {
+                        "safe_to_remove_worktree": False,
+                        "worktree_path": "/tmp/dirty-wt",
+                    },
+                }
+            ],
+            "reviewer_scratch_entries": [],
+        }
+        patch(
+            "mcp_server.get_profile",
+            return_value={
+                "profile_name": "prgs-reconciler",
+                "role": "reconciler",
+                "allowed_operations": [
+                    "gitea.read",
+                    "gitea.branch.delete",
+                ],
+                "forbidden_operations": [],
+            },
+        ).start()
+        patch("mcp_server.api_get_all", return_value=[]).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.build_reconciliation_report",
+            return_value=report,
+        ).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.discover_reviewer_scratch_worktrees",
+            return_value=[],
+        ).start()
+        patch(
+            "mcp_server.audit_reconciliation_mode.check_cleanup_execution_allowed",
+            return_value=(True, []),
+        ).start()
+        patch("mcp_server.verify_preflight_purity", return_value=None).start()
+        patch(
+            "mcp_server._collect_branch_ownership_records",
+            side_effect=fake_collect,
+        ).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.remove_local_worktree",
+            side_effect=lambda *a, **k: remove_calls.append(k) or {
+                "success": True,
+                "performed": True,
+            },
+        ).start()
+        self.mock_api.side_effect = lambda *a, **k: {}
+
+        res = gitea_reconcile_merged_cleanups(
+            dry_run=False,
+            execute_confirmed=True,
+            remote="prgs",
+        )
+        actions = res.get("actions") or []
+        self.assertEqual(remove_calls, [])
+        self.assertFalse(
+            any(a.get("action") == "remove_local_worktree" for a in actions)
+        )
+        deletes = [
+            a for a in actions if a.get("action") == "delete_remote_branch"
+        ]
+        self.assertEqual(len(deletes), 1)
+        self.assertFalse(deletes[0].get("success"))
+        self.assertEqual(deletes[0].get("blocker_kind"), "active_branch_ownership")
+        self.assertIn(
+            guard.OWNERSHIP_CATEGORY_WORKTREE_BINDING,
+            deletes[0].get("blocking_categories") or [],
+        )
+
+    def test_issue_851_idempotent_resume_when_worktree_already_absent(self):
+        """#851: partial failures remain resumable and idempotent."""
+        from mcp_server import gitea_reconcile_merged_cleanups
+
+        branch = "fix/issue-851-resume"
+        ownership_calls = []
+
+        def fake_collect(**kwargs):
+            ownership_calls.append(kwargs)
+            return {"records": [], "inventory_error": False}
+
+        def fake_remove(project_root, branch, worktree_path=None):
+            return {
+                "success": False,
+                "performed": False,
+                "message": f"worktree not found: {worktree_path}",
+            }
+
+        def fake_probe(h, o, r, auth, br):
+            return guard.classify_branch_readback_http_status(
+                404, not_found_scope=guard.NOT_FOUND_SCOPE_BRANCH
+            )
+
+        report = {
+            "entries": [
+                {
+                    "pr_number": 851,
+                    "head_branch": branch,
+                    "remote_branch": {"safe_to_delete_remote": True},
+                    "local_worktree": {
+                        "safe_to_remove_worktree": True,
+                        "worktree_path": "/tmp/already-gone",
+                    },
+                }
+            ],
+            "reviewer_scratch_entries": [],
+        }
+        patch(
+            "mcp_server.get_profile",
+            return_value={
+                "profile_name": "prgs-reconciler",
+                "role": "reconciler",
+                "allowed_operations": [
+                    "gitea.read",
+                    "gitea.branch.delete",
+                ],
+                "forbidden_operations": [],
+            },
+        ).start()
+        patch("mcp_server.api_get_all", return_value=[]).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.build_reconciliation_report",
+            return_value=report,
+        ).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.discover_reviewer_scratch_worktrees",
+            return_value=[],
+        ).start()
+        patch(
+            "mcp_server.audit_reconciliation_mode.check_cleanup_execution_allowed",
+            return_value=(True, []),
+        ).start()
+        patch("mcp_server.verify_preflight_purity", return_value=None).start()
+        patch(
+            "mcp_server._collect_branch_ownership_records",
+            side_effect=fake_collect,
+        ).start()
+        patch("mcp_server._probe_remote_branch", side_effect=fake_probe).start()
+        patch(
+            "mcp_server.merged_cleanup_reconcile.remove_local_worktree",
+            side_effect=fake_remove,
+        ).start()
+        self.mock_api.side_effect = lambda *a, **k: {}
+
+        res = gitea_reconcile_merged_cleanups(
+            dry_run=False,
+            execute_confirmed=True,
+            remote="prgs",
+        )
+        actions = res.get("actions") or []
+        removes = [a for a in actions if a.get("action") == "remove_local_worktree"]
+        deletes = [a for a in actions if a.get("action") == "delete_remote_branch"]
+        self.assertEqual(len(removes), 1)
+        self.assertFalse(removes[0].get("success"))
+        self.assertEqual(len(deletes), 1)
+        self.assertTrue(deletes[0].get("success"))
+        self.assertTrue(deletes[0].get("after_worktree_removal"))
+        self.assertTrue(ownership_calls)
+
 
 
 if __name__ == "__main__":

tests/test_issue_843_cross_role_handoff.py

@@ -0,0 +1,682 @@
+"""Cross-role allocation handoff consumable by independent workers (#843).
+
+Regression coverage for the controller→required-role consume path:
+
+* controller allocates author work; independent author adopts successfully
+* author adoption succeeds after allocating controller process exits
+* author adoption without sharing controller session identity
+* wrong-role adoption rejected
+* concurrent/second adoption rejected without state corruption
+* terminal allocation adoption rejected
+* successful adoption produces authoritative ownership evidence
+* genuine abandoned-lease recovery remains valid
+* process_work_queue / allocate results include consume identifiers
+* same-role allocation behavior remains compatible
+"""
+
+from __future__ import annotations
+
+import os
+import tempfile
+import unittest
+from datetime import timedelta
+from unittest.mock import patch
+
+from allocator_service import (
+    ALLOCATION_MODE_CROSS_ROLE,
+    ALLOCATION_MODE_ROLE_SCOPED,
+    OUTCOME_ASSIGNED,
+    ROLE_AUTHOR,
+    ROLE_CONTROLLER,
+    ROLE_REVIEWER,
+    WorkCandidate,
+    allocate_next_work,
+)
+from control_plane_db import ControlPlaneDB, ForeignLeaseError, _ts, _utc_now
+import lease_lifecycle as ll
+
+
+class CrossRoleHandoffTest(unittest.TestCase):
+    def setUp(self) -> None:
+        self._tmp = tempfile.TemporaryDirectory()
+        self.db_path = os.path.join(self._tmp.name, "cp.sqlite3")
+        self.db = ControlPlaneDB(self.db_path)
+        self.db.upsert_session(
+            session_id="ctrl-session",
+            role="controller",
+            profile="prgs-controller",
+            pid=99999999,  # dead-looking pid
+        )
+        self.db.upsert_session(
+            session_id="author-worker",
+            role="author",
+            profile="prgs-author",
+            pid=os.getpid(),
+        )
+        self.db.upsert_session(
+            session_id="author-worker-2",
+            role="author",
+            profile="prgs-author",
+            pid=os.getpid(),
+        )
+        self.db.upsert_session(
+            session_id="reviewer-worker",
+            role="reviewer",
+            profile="prgs-reviewer",
+            pid=os.getpid(),
+        )
+        self.wt = self._tmp.name
+
+    def tearDown(self) -> None:
+        self._tmp.cleanup()
+
+    def _ready_issue(self, number: int = 843, title: str = "handoff target") -> WorkCandidate:
+        return WorkCandidate(
+            kind="issue",
+            number=number,
+            labels=("status:ready", "type:bug"),
+            title=title,
+            priority=20,
+        )
+
+    def _controller_allocate(self, number: int = 843, **kwargs):
+        defaults = dict(
+            db=self.db,
+            session_id="ctrl-session",
+            role=ROLE_CONTROLLER,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            candidates=[self._ready_issue(number)],
+            apply=True,
+            profile_name="prgs-controller",
+            username="controller-user",
+            allocation_mode=ALLOCATION_MODE_CROSS_ROLE,
+        )
+        defaults.update(kwargs)
+        return allocate_next_work(**defaults)
+
+    def test_controller_allocates_author_independent_author_adopts(self) -> None:
+        res = self._controller_allocate()
+        self.assertEqual(res["outcome"], OUTCOME_ASSIGNED)
+        self.assertEqual(res["required_role"], ROLE_AUTHOR)
+        self.assertIn("consume_allocation", res)
+        consume = res["consume_allocation"]
+        self.assertEqual(consume["tool"], "gitea_adopt_workflow_lease")
+        self.assertEqual(consume["required_role"], ROLE_AUTHOR)
+        self.assertFalse(consume["controller_session_required"])
+        lid = res["assignment"]["lease_id"]
+        self.assertEqual(consume["lease_id"], lid)
+        self.assertIn(lid, res["next_valid_command"])
+
+        adopted = ll.adopt_lease(
+            self.db,
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        self.assertTrue(adopted["success"])
+        self.assertEqual(adopted["outcome"], "adopted_cross_role_handoff")
+        self.assertEqual(adopted["adopted_by_session_id"], "author-worker")
+        self.assertEqual(adopted["adopted_from_session_id"], "ctrl-session")
+        raw = adopted["read_after_write"]
+        self.assertEqual(raw["session_id"], "author-worker")
+        self.assertEqual(raw["adopted_by_session_id"], "author-worker")
+        self.assertEqual(raw["status"], "active")
+        self.assertEqual(raw["phase"], "adopted")
+
+        # Authoritative re-read
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], "author-worker")
+        self.assertEqual(state["lease"]["adopted_by_session_id"], "author-worker")
+        self.assertEqual(state["assignment"]["session_id"], "author-worker")
+        self.assertEqual(state["provenance"]["handoff_status"], "adopted")
+
+    def test_author_adoption_after_controller_process_exits(self) -> None:
+        res = self._controller_allocate(number=900)
+        lid = res["assignment"]["lease_id"]
+        # Force owner_pid dead + freshness stale_dead_process
+        import sqlite3
+
+        conn = sqlite3.connect(self.db_path)
+        try:
+            conn.execute(
+                "UPDATE leases SET owner_pid = 99999999 WHERE lease_id = ?",
+                (lid,),
+            )
+            conn.commit()
+        finally:
+            conn.close()
+        state = self.db.get_lease_workflow_state(lid)
+        fr = ll.classify_lease_freshness(
+            state["lease"], pid_checker=lambda _p: False
+        )
+        self.assertEqual(fr["freshness"], "stale_dead_process")
+
+        adopted = ll.adopt_lease(
+            self.db,
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        self.assertEqual(adopted["outcome"], "adopted_cross_role_handoff")
+        self.assertEqual(adopted["adopted_by_session_id"], "author-worker")
+        # No abandon required
+        state2 = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state2["lease"]["status"], "active")
+        self.assertNotEqual(state2["lease"]["status"], "abandoned")
+
+    def test_adoption_without_sharing_controller_session_identity(self) -> None:
+        res = self._controller_allocate(number=901)
+        lid = res["assignment"]["lease_id"]
+        adopted = ll.adopt_lease(
+            self.db,
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        self.assertNotEqual(adopted["adopted_by_session_id"], "ctrl-session")
+        self.assertFalse(adopted["same_owner"])
+        self.assertEqual(adopted["adopted_from_session_id"], "ctrl-session")
+
+    def test_wrong_role_adoption_rejected(self) -> None:
+        res = self._controller_allocate(number=902)
+        lid = res["assignment"]["lease_id"]
+        with self.assertRaises(ll.LeaseLifecycleError) as ctx:
+            ll.adopt_lease(
+                self.db,
+                lease_id=lid,
+                adopter_session_id="reviewer-worker",
+                role=ROLE_REVIEWER,
+            )
+        self.assertIn("wrong role", str(ctx.exception).lower())
+        # State unchanged
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], "ctrl-session")
+        self.assertIsNone(state["lease"].get("adopted_by_session_id") or None)
+        self.assertEqual(state["provenance"]["handoff_status"], "pending")
+
+    def test_second_adoption_rejected_without_corruption(self) -> None:
+        res = self._controller_allocate(number=903)
+        lid = res["assignment"]["lease_id"]
+        first = ll.adopt_lease(
+            self.db,
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        self.assertEqual(first["outcome"], "adopted_cross_role_handoff")
+        with self.assertRaises(ll.LeaseLifecycleError):
+            ll.adopt_lease(
+                self.db,
+                lease_id=lid,
+                adopter_session_id="author-worker-2",
+                role=ROLE_AUTHOR,
+                worktree_path=self.wt,
+            )
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], "author-worker")
+        self.assertEqual(state["lease"]["adopted_by_session_id"], "author-worker")
+        self.assertEqual(state["assignment"]["session_id"], "author-worker")
+        self.assertEqual(state["lease"]["status"], "active")
+
+    def test_terminal_allocation_adoption_rejected(self) -> None:
+        res = self._controller_allocate(number=904)
+        lid = res["assignment"]["lease_id"]
+        # Abandon as terminal
+        proof = ll.AbandonProof(
+            dead_process=True,
+            missing_worktree=True,
+            no_open_pr=True,
+            no_live_mutation_risk=True,
+            owner_pid=99999999,
+            worktree_path="/nonexistent/for-843",
+        )
+        # Attach dead pid / missing wt for abandon eligibility
+        import sqlite3
+
+        conn = sqlite3.connect(self.db_path)
+        try:
+            conn.execute(
+                "UPDATE leases SET owner_pid = 99999999, worktree_path = ? WHERE lease_id = ?",
+                ("/nonexistent/for-843", lid),
+            )
+            conn.commit()
+        finally:
+            conn.close()
+        abandoned = ll.abandon_lease(
+            self.db,
+            lease_id=lid,
+            requester_session_id="author-worker",
+            proof=proof,
+        )
+        self.assertEqual(abandoned["outcome"], "abandoned")
+        with self.assertRaises(ll.LeaseLifecycleError) as ctx:
+            ll.adopt_lease(
+                self.db,
+                lease_id=lid,
+                adopter_session_id="author-worker",
+                role=ROLE_AUTHOR,
+            )
+        self.assertIn("abandoned", str(ctx.exception).lower())
+
+    def test_successful_adoption_read_after_write_ownership(self) -> None:
+        res = self._controller_allocate(number=905)
+        lid = res["assignment"]["lease_id"]
+        adopted = ll.adopt_lease(
+            self.db,
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        raw = adopted["read_after_write"]
+        self.assertEqual(raw["lease_id"], lid)
+        self.assertEqual(raw["session_id"], "author-worker")
+        self.assertEqual(raw["adopted_by_session_id"], "author-worker")
+        self.assertEqual(raw["adopted_from_session_id"], "ctrl-session")
+        # Re-fetch proves durable write
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], raw["session_id"])
+        self.assertEqual(
+            state["lease"]["adopted_by_session_id"], raw["adopted_by_session_id"]
+        )
+
+    def test_genuine_abandoned_recovery_still_valid(self) -> None:
+        """Same-role author lease abandoned remains reclaimable via abandon path."""
+        same = allocate_next_work(
+            self.db,
+            session_id="author-worker",
+            role=ROLE_AUTHOR,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            candidates=[self._ready_issue(906, "same-role")],
+            apply=True,
+            profile_name="prgs-author",
+            username="author-user",
+            allocation_mode=ALLOCATION_MODE_ROLE_SCOPED,
+        )
+        self.assertEqual(same["outcome"], OUTCOME_ASSIGNED)
+        lid = same["assignment"]["lease_id"]
+        import sqlite3
+
+        conn = sqlite3.connect(self.db_path)
+        try:
+            conn.execute(
+                "UPDATE leases SET owner_pid = 99999999, worktree_path = ? WHERE lease_id = ?",
+                ("/nonexistent/same-role", lid),
+            )
+            conn.commit()
+        finally:
+            conn.close()
+        proof = ll.AbandonProof(
+            dead_process=True,
+            missing_worktree=True,
+            no_open_pr=True,
+            no_live_mutation_risk=True,
+            owner_pid=99999999,
+            worktree_path="/nonexistent/same-role",
+        )
+        abandoned = ll.abandon_lease(
+            self.db,
+            lease_id=lid,
+            requester_session_id="author-worker-2",
+            proof=proof,
+        )
+        self.assertEqual(abandoned["outcome"], "abandoned")
+        # Foreign author cannot handoff-consume an abandoned non-handoff lease
+        with self.assertRaises(ll.LeaseLifecycleError):
+            ll.adopt_lease(
+                self.db,
+                lease_id=lid,
+                adopter_session_id="author-worker-2",
+                role=ROLE_AUTHOR,
+            )
+        # Reclaim path still works for expired/abandoned after force-expire
+        reclaimed = ll.reclaim_expired_lease(
+            self.db,
+            lease_id=lid,
+            session_id="author-worker-2",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        self.assertEqual(reclaimed["outcome"], "reclaimed")
+        self.assertEqual(reclaimed["assignment"]["session_id"], "author-worker-2")
+
+    def test_allocate_payload_includes_consume_identifiers(self) -> None:
+        res = self._controller_allocate(number=907)
+        self.assertIn("consume_allocation", res)
+        c = res["consume_allocation"]
+        for key in (
+            "tool",
+            "lease_id",
+            "assignment_id",
+            "required_role",
+            "required_profile",
+            "required_namespace",
+            "instructions",
+            "handoff_status",
+        ):
+            self.assertIn(key, c)
+        self.assertEqual(c["required_namespace"], "gitea-author")
+        self.assertEqual(c["required_profile"], "prgs-author")
+        self.assertIn("gitea_adopt_workflow_lease", c["instructions"])
+        self.assertTrue(res["lease_proof"]["cross_role_handoff"])
+        self.assertEqual(res["lease_proof"]["handoff_status"], "pending")
+
+    def test_same_role_allocation_remains_compatible(self) -> None:
+        res = allocate_next_work(
+            self.db,
+            session_id="author-worker",
+            role=ROLE_AUTHOR,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            candidates=[self._ready_issue(908)],
+            apply=True,
+            profile_name="prgs-author",
+            username="author-user",
+        )
+        self.assertEqual(res["outcome"], OUTCOME_ASSIGNED)
+        self.assertNotIn("consume_allocation", res)
+        lid = res["assignment"]["lease_id"]
+        state = self.db.get_lease_workflow_state(lid)
+        # No cross-role handoff provenance
+        prov = state.get("provenance") or {}
+        self.assertFalse(prov.get("cross_role_handoff"))
+        # Owner resume still works
+        resume = ll.adopt_lease(
+            self.db,
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+        )
+        self.assertTrue(resume["same_owner"])
+        self.assertEqual(resume["outcome"], "adopted_owner_resume")
+
+    def test_inspect_points_required_role_at_consume(self) -> None:
+        res = self._controller_allocate(number=909)
+        lid = res["assignment"]["lease_id"]
+        decision = ll.inspect_lease(
+            self.db, lid, caller_session_id="author-worker"
+        )
+        self.assertEqual(
+            decision["safe_next_action"], ll.SAFE_CONSUME_CROSS_ROLE
+        )
+        self.assertFalse(decision["block"])
+        self.assertEqual(decision["required_role"], ROLE_AUTHOR)
+
+    def test_db_cas_rejects_concurrent_second_consume(self) -> None:
+        res = self._controller_allocate(number=910)
+        lid = res["assignment"]["lease_id"]
+        # First consume via DB layer directly
+        first = self.db.adopt_lease(
+            lease_id=lid,
+            adopter_session_id="author-worker",
+            role=ROLE_AUTHOR,
+            worktree_path=self.wt,
+            provenance={
+                "cross_role_handoff": True,
+                "handoff_status": "adopted",
+                "required_role": "author",
+            },
+        )
+        self.assertEqual(first["outcome"], "adopted_cross_role_handoff")
+        # Second CAS must fail
+        with self.assertRaises(ForeignLeaseError):
+            self.db.adopt_lease(
+                lease_id=lid,
+                adopter_session_id="author-worker-2",
+                role=ROLE_AUTHOR,
+                worktree_path=self.wt,
+                provenance={
+                    "cross_role_handoff": True,
+                    "handoff_status": "pending",
+                    "required_role": "author",
+                },
+            )
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], "author-worker")
+
+
+class MCPBoundaryAdoptRoleBindingTest(unittest.TestCase):
+    """#843 F1: MCP-boundary role binding for ``gitea_adopt_workflow_lease``.
+
+    The library-level wrong-role test calls ``lease_lifecycle.adopt_lease``
+    directly. These tests prove the MCP entry point derives the adopter role
+    authoritatively from the active authenticated profile and rejects any
+    caller-supplied role that disagrees, so a reviewer/merger profile cannot
+    consume an author handoff by passing ``role="author"``.
+    """
+
+    AUTHOR_PROFILE = {
+        "profile_name": "prgs-author",
+        "role": "author",
+        "allowed_operations": [
+            "gitea.read",
+            "gitea.pr.create",
+            "gitea.branch.push",
+        ],
+        "forbidden_operations": [],
+    }
+    REVIEWER_PROFILE = {
+        "profile_name": "prgs-reviewer",
+        "role": "reviewer",
+        "allowed_operations": [
+            "gitea.read",
+            "gitea.pr.review",
+            "gitea.pr.approve",
+            "gitea.pr.request_changes",
+        ],
+        "forbidden_operations": ["gitea.pr.create", "gitea.branch.push"],
+    }
+    MERGER_PROFILE = {
+        "profile_name": "prgs-merger",
+        "role": "merger",
+        "allowed_operations": ["gitea.read", "gitea.pr.merge"],
+        "forbidden_operations": ["gitea.pr.create", "gitea.branch.push"],
+    }
+    FOREIGN_AUTHOR_PROFILE = {
+        "profile_name": "dadeschools-author",
+        "role": "author",
+        "allowed_operations": [
+            "gitea.read",
+            "gitea.pr.create",
+            "gitea.branch.push",
+        ],
+        "forbidden_operations": [],
+    }
+
+    def setUp(self) -> None:
+        self._tmp = tempfile.TemporaryDirectory()
+        self.db_path = os.path.join(self._tmp.name, "cp.sqlite3")
+        self.db = ControlPlaneDB(self.db_path)
+        self.db.upsert_session(
+            session_id="ctrl-session",
+            role="controller",
+            profile="prgs-controller",
+            pid=99999999,
+        )
+        self.db.upsert_session(
+            session_id="author-worker",
+            role="author",
+            profile="prgs-author",
+            pid=os.getpid(),
+        )
+        self.wt = self._tmp.name
+
+    def tearDown(self) -> None:
+        self._tmp.cleanup()
+
+    def _ready_issue(self, number: int) -> WorkCandidate:
+        return WorkCandidate(
+            kind="issue",
+            number=number,
+            labels=("status:ready", "type:bug"),
+            title="handoff target",
+            priority=20,
+        )
+
+    def _handoff_lease(self, number: int = 843) -> str:
+        res = allocate_next_work(
+            db=self.db,
+            session_id="ctrl-session",
+            role=ROLE_CONTROLLER,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            candidates=[self._ready_issue(number)],
+            apply=True,
+            profile_name="prgs-controller",
+            username="controller-user",
+            allocation_mode=ALLOCATION_MODE_CROSS_ROLE,
+        )
+        self.assertEqual(res["outcome"], OUTCOME_ASSIGNED)
+        self.assertEqual(res["required_role"], ROLE_AUTHOR)
+        return res["assignment"]["lease_id"]
+
+    def _call_adopt_tool(self, profile: dict, **kwargs):
+        import gitea_mcp_server as mcp_server
+
+        with (
+            patch.object(mcp_server, "get_profile", return_value=profile),
+            patch.object(
+                mcp_server,
+                "_control_plane_db_or_error",
+                return_value=(self.db, []),
+            ),
+        ):
+            return mcp_server.gitea_adopt_workflow_lease(
+                remote="prgs", **kwargs
+            )
+
+    def _assert_handoff_untouched(self, lease_id: str) -> None:
+        state = self.db.get_lease_workflow_state(lease_id)
+        self.assertEqual(state["lease"]["session_id"], "ctrl-session")
+        self.assertIsNone(state["lease"].get("adopted_by_session_id") or None)
+        self.assertEqual(state["lease"]["status"], "active")
+        self.assertEqual(state["provenance"]["handoff_status"], "pending")
+
+    def test_reviewer_profile_cannot_consume_author_handoff_via_role_author(
+        self,
+    ) -> None:
+        lid = self._handoff_lease(920)
+        result = self._call_adopt_tool(
+            self.REVIEWER_PROFILE,
+            lease_id=lid,
+            session_id="reviewer-worker",
+            role="author",
+            worktree_path=self.wt,
+        )
+        self.assertFalse(result["success"])
+        self.assertEqual(result["outcome"], "blocked")
+        self.assertEqual(result["profile_role_kind"], "reviewer")
+        self.assertEqual(result["supplied_role"], "author")
+        self.assertIn("does not match", result["reasons"][0])
+        self._assert_handoff_untouched(lid)
+
+    def test_merger_profile_cannot_consume_author_handoff_via_role_author(
+        self,
+    ) -> None:
+        lid = self._handoff_lease(921)
+        result = self._call_adopt_tool(
+            self.MERGER_PROFILE,
+            lease_id=lid,
+            session_id="merger-worker",
+            role="author",
+            worktree_path=self.wt,
+        )
+        self.assertFalse(result["success"])
+        self.assertEqual(result["outcome"], "blocked")
+        self.assertEqual(result["profile_role_kind"], "merger")
+        self._assert_handoff_untouched(lid)
+
+    def test_reviewer_profile_rejected_without_role_argument(self) -> None:
+        """Even without a spoofed role, the profile-derived role binds."""
+        lid = self._handoff_lease(922)
+        result = self._call_adopt_tool(
+            self.REVIEWER_PROFILE,
+            lease_id=lid,
+            session_id="reviewer-worker",
+            worktree_path=self.wt,
+        )
+        self.assertFalse(result["success"])
+        self.assertEqual(result["outcome"], "blocked")
+        self.assertIn("wrong role", result["reasons"][0].lower())
+        self._assert_handoff_untouched(lid)
+
+    def test_author_profile_mismatching_supplied_role_rejected(self) -> None:
+        lid = self._handoff_lease(923)
+        result = self._call_adopt_tool(
+            self.AUTHOR_PROFILE,
+            lease_id=lid,
+            session_id="author-worker",
+            role="reviewer",
+            worktree_path=self.wt,
+        )
+        self.assertFalse(result["success"])
+        self.assertEqual(result["outcome"], "blocked")
+        self.assertEqual(result["profile_role_kind"], "author")
+        self.assertEqual(result["supplied_role"], "reviewer")
+        self._assert_handoff_untouched(lid)
+
+    def test_foreign_profile_name_rejected_for_author_handoff(self) -> None:
+        """Provenance required_profile binds even when the role matches."""
+        lid = self._handoff_lease(924)
+        result = self._call_adopt_tool(
+            self.FOREIGN_AUTHOR_PROFILE,
+            lease_id=lid,
+            session_id="foreign-author-worker",
+            worktree_path=self.wt,
+        )
+        self.assertFalse(result["success"])
+        self.assertEqual(result["outcome"], "blocked")
+        self.assertIn("wrong profile", result["reasons"][0].lower())
+        self._assert_handoff_untouched(lid)
+
+    def test_author_profile_consumes_author_handoff(self) -> None:
+        lid = self._handoff_lease(925)
+        result = self._call_adopt_tool(
+            self.AUTHOR_PROFILE,
+            lease_id=lid,
+            session_id="author-worker",
+            role="author",
+            worktree_path=self.wt,
+        )
+        self.assertTrue(result["success"])
+        self.assertEqual(result["outcome"], "adopted_cross_role_handoff")
+        self.assertEqual(result["adopted_by_session_id"], "author-worker")
+        self.assertEqual(result["adopted_from_session_id"], "ctrl-session")
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], "author-worker")
+        self.assertEqual(
+            state["lease"]["adopted_by_session_id"], "author-worker"
+        )
+        self.assertEqual(state["assignment"]["session_id"], "author-worker")
+        self.assertEqual(state["provenance"]["handoff_status"], "adopted")
+
+    def test_author_profile_consumes_author_handoff_without_role_argument(
+        self,
+    ) -> None:
+        lid = self._handoff_lease(926)
+        result = self._call_adopt_tool(
+            self.AUTHOR_PROFILE,
+            lease_id=lid,
+            session_id="author-worker",
+            worktree_path=self.wt,
+        )
+        self.assertTrue(result["success"])
+        self.assertEqual(result["outcome"], "adopted_cross_role_handoff")
+        state = self.db.get_lease_workflow_state(lid)
+        self.assertEqual(state["lease"]["session_id"], "author-worker")
+        self.assertEqual(state["lease"]["role"], "author")
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_merged_cleanup_reconcile.py

@@ -12,6 +12,59 @@ import merged_cleanup_reconcile as mcr  # noqa: E402
 
 
 class TestMergedCleanupAssessment(unittest.TestCase):
+    def test_issue_851_plan_order_worktree_then_reassess_then_remote(self):
+        """#851 dry-run plan: remove worktree, reassess ownership, then remote."""
+        plan = mcr.plan_cleanup_execution_order(
+            remote_assessment={"safe_to_delete_remote": True},
+            local_assessment={"safe_to_remove_worktree": True},
+        )
+        actions = [s["action"] for s in plan]
+        self.assertEqual(
+            actions,
+            [
+                "remove_local_worktree",
+                "reassess_branch_ownership",
+                "delete_remote_branch",
+            ],
+        )
+        self.assertEqual(plan[0]["phase"], 1)
+        self.assertEqual(plan[-1]["phase"], 3)
+        self.assertIn("independently_safe", plan[0]["reason"])
+        self.assertIn("reassessment", plan[-1]["reason"])
+
+    def test_issue_851_plan_remote_only_when_worktree_not_safe(self):
+        plan = mcr.plan_cleanup_execution_order(
+            remote_assessment={"safe_to_delete_remote": True},
+            local_assessment={"safe_to_remove_worktree": False},
+        )
+        self.assertEqual([s["action"] for s in plan], ["delete_remote_branch"])
+        self.assertNotIn("reassess_branch_ownership", [s["action"] for s in plan])
+
+    def test_issue_851_plan_worktree_only_when_remote_not_safe(self):
+        plan = mcr.plan_cleanup_execution_order(
+            remote_assessment={"safe_to_delete_remote": False},
+            local_assessment={"safe_to_remove_worktree": True},
+        )
+        self.assertEqual([s["action"] for s in plan], ["remove_local_worktree"])
+
+    def test_issue_851_entry_includes_planned_execution_order(self):
+        entry = mcr.build_pr_cleanup_entry(
+            pr={
+                "number": 848,
+                "title": "Closes #844",
+                "body": "",
+                "merged_at": "2026-07-23T00:00:00Z",
+                "head": {"ref": "fix/issue-844-x", "sha": "a" * 40},
+            },
+            project_root="/tmp/not-a-real-root",
+            open_pr_heads=set(),
+            remote_branch_exists=True,
+            head_on_master=True,
+            delete_capability_allowed=True,
+        )
+        self.assertIn("planned_execution_order", entry)
+        self.assertIsInstance(entry["planned_execution_order"], list)
+
     def test_extract_linked_issue_from_closes(self):
         issue = mcr.extract_linked_issue(
             "feat: cleanup (Closes #269)",

tests/test_webui_shell.py

@@ -0,0 +1,135 @@
+"""Tests for the Phase 1 operator console application shell (#638)."""
+import sys
+import unittest
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+
+from starlette.routing import Route
+from starlette.testclient import TestClient
+
+from webui import layout
+from webui.app import create_app
+from webui.nav import NAV_GROUPS, STUB_PAGES, nav_hrefs
+
+
+class TestShellNav(unittest.TestCase):
+    def setUp(self):
+        self.client = TestClient(create_app())
+
+    def test_nav_group_labels_present(self):
+        text = self.client.get("/").text
+        for group in NAV_GROUPS:
+            with self.subTest(group=group.label):
+                self.assertIn(f">{group.label}<", text)
+
+    def test_phase1_group_labels_cover_expected_ia(self):
+        labels = {group.label for group in NAV_GROUPS}
+        for expected in (
+            "Health",
+            "Traffic",
+            "Runtime/Sessions",
+            "Projects",
+            "Inventory",
+            "Timeline",
+            "Policy",
+            "Insights",
+        ):
+            with self.subTest(label=expected):
+                self.assertIn(expected, labels)
+
+    def test_every_nav_href_resolves_to_a_get_route(self):
+        app = create_app()
+        get_paths = {
+            route.path
+            for route in app.routes
+            if isinstance(route, Route) and "GET" in route.methods
+        }
+        for href in nav_hrefs():
+            with self.subTest(href=href):
+                self.assertIn(href, get_paths, f"nav href {href} has no GET route")
+
+    def test_legacy_hrefs_still_navigable(self):
+        text = self.client.get("/").text
+        for href in ("/queue", "/projects", "/prompts", "/runtime",
+                     "/audit", "/worktrees", "/leases", "/actions"):
+            with self.subTest(href=href):
+                self.assertIn(f'href="{href}"', text)
+
+
+class TestShellBadges(unittest.TestCase):
+    def setUp(self):
+        self.client = TestClient(create_app())
+
+    def test_mode_badge_present(self):
+        self.assertIn("mode: read-only", self.client.get("/").text)
+
+    def test_environment_badge_present(self):
+        self.assertIn("env:", self.client.get("/").text)
+
+    def test_default_environment_is_local(self):
+        self.assertEqual(layout.environment_label(), "local")
+
+    def test_remote_bind_reports_remote_environment(self):
+        import os
+
+        prior = os.environ.get("WEBUI_HOST")
+        os.environ["WEBUI_HOST"] = "10.0.0.5"
+        try:
+            self.assertEqual(layout.environment_label(), "remote")
+        finally:
+            if prior is None:
+                os.environ.pop("WEBUI_HOST", None)
+            else:
+                os.environ["WEBUI_HOST"] = prior
+
+    def test_docs_link_present(self):
+        text = self.client.get("/").text
+        self.assertIn(layout.DOCS_URL, text)
+        self.assertIn(">Docs<", text)
+
+
+class TestShellStubs(unittest.TestCase):
+    def setUp(self):
+        self.client = TestClient(create_app())
+
+    def test_stub_routes_render_200(self):
+        for path, (title, _desc) in STUB_PAGES.items():
+            with self.subTest(path=path):
+                response = self.client.get(path)
+                self.assertEqual(response.status_code, 200, path)
+                self.assertIn(title, response.text)
+                self.assertIn("placeholder", response.text)
+
+    def test_stub_routes_are_read_only(self):
+        for path in STUB_PAGES:
+            with self.subTest(path=path):
+                response = self.client.post(path)
+                self.assertEqual(response.status_code, 405)
+                self.assertEqual(response.json()["error"], "read-only-mvp")
+
+    def test_stub_pages_carry_nav_and_badges(self):
+        response = self.client.get("/inventory")
+        self.assertIn("mode: read-only", response.text)
+        self.assertIn('href="/queue"', response.text)
+
+
+class TestShellHome(unittest.TestCase):
+    def setUp(self):
+        self.client = TestClient(create_app())
+
+    def test_home_summarizes_console(self):
+        text = self.client.get("/").text
+        self.assertIn("Operator console", text)
+        self.assertIn("Phase 1", text)
+
+    def test_home_links_legacy_pages(self):
+        text = self.client.get("/").text
+        self.assertIn("MVP legacy pages", text)
+        for href in ("/queue", "/audit", "/leases"):
+            with self.subTest(href=href):
+                self.assertIn(f'href="{href}"', text)
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_webui_system_health.py

@@ -0,0 +1,499 @@
+"""Tests for the read-only system-health API (#634).
+
+Covers the acceptance criteria directly: a structured payload with readiness
+and a dependency list (AC1), version and uptime when knowable (AC2), stale
+runtime reported without a false mutation-safe claim (AC3), and the healthy /
+degraded-dependency / redaction cases (AC4).
+"""
+import json
+import os
+import sqlite3
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+from unittest import mock
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+
+from starlette.testclient import TestClient
+
+import control_plane_db
+from webui.app import create_app
+from webui.deployment_boundary import scan_text_for_client_secrets
+from webui.system_health import (
+    API_PATH,
+    STATUS_DEGRADED,
+    STATUS_DOWN,
+    STATUS_OK,
+    STATUS_SKIPPED,
+    DependencyProbe,
+    StaleRuntime,
+    assess_stale_runtime,
+    clear_probe_cache,
+    load_system_health,
+    namespace_summaries,
+    probe_control_plane_db,
+    probe_gitea,
+    process_uptime,
+    redact,
+    redact_url,
+    snapshot_to_dict,
+)
+
+
+def _probe(name, status, *, required=True, detail="detail", kind="test"):
+    return DependencyProbe(
+        name=name,
+        kind=kind,
+        status=status,
+        detail=detail,
+        required=required,
+        latency_ms=1.5,
+        metadata={},
+    )
+
+
+_ALL_HEALTHY = (
+    _probe("control_plane_db", STATUS_OK, kind="sqlite"),
+    _probe("repository", STATUS_OK, kind="git"),
+    _probe("gitea", STATUS_OK, required=False, kind="http"),
+)
+
+_CLEAN_PARITY = StaleRuntime(
+    daemon_head="abc123",
+    checkout_head="abc123",
+    remote_head="abc123",
+    stale=False,
+    determinable=True,
+    mutation_safe=True,
+    reasons=(),
+)
+
+
+class CleanParityMixin:
+    """Pin parity for tests about aggregation rather than staleness.
+
+    Without this the assertions depend on the real checkout: a worktree whose
+    branch is ahead of its upstream is genuinely stale, which would degrade the
+    overall status and make these cases fail for an unrelated reason.
+    """
+
+    def setUp(self):
+        super().setUp()
+        patcher = mock.patch(
+            "webui.system_health.assess_stale_runtime",
+            return_value=_CLEAN_PARITY,
+        )
+        patcher.start()
+        self.addCleanup(patcher.stop)
+
+
+class TestDependencyAggregation(CleanParityMixin, unittest.TestCase):
+    """AC1 — readiness and dependency list derived from probe results."""
+
+    def test_all_healthy_is_ok_and_ready(self):
+        snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="abc123")
+        self.assertEqual(snapshot.status, STATUS_OK)
+        self.assertTrue(snapshot.ready)
+        self.assertTrue(snapshot.readiness_complete)
+        self.assertEqual(snapshot.readiness_reasons, ())
+        self.assertEqual(len(snapshot.dependencies), 3)
+
+    def test_required_dependency_down_blocks_readiness(self):
+        probes = (
+            _probe("control_plane_db", STATUS_DOWN, detail="file missing", kind="sqlite"),
+            _probe("repository", STATUS_OK, kind="git"),
+            _probe("gitea", STATUS_OK, required=False, kind="http"),
+        )
+        snapshot = load_system_health(probes=probes, daemon_head="abc123")
+        self.assertEqual(snapshot.status, STATUS_DOWN)
+        self.assertFalse(snapshot.ready)
+        self.assertTrue(
+            any("control_plane_db" in reason for reason in snapshot.readiness_reasons)
+        )
+
+    def test_optional_dependency_down_degrades_but_stays_ready(self):
+        """A failing optional probe must not claim the process itself is unready."""
+        probes = (
+            _probe("control_plane_db", STATUS_OK, kind="sqlite"),
+            _probe("repository", STATUS_OK, kind="git"),
+            _probe("gitea", STATUS_DOWN, required=False, detail="timeout", kind="http"),
+        )
+        snapshot = load_system_health(probes=probes, daemon_head="abc123")
+        self.assertEqual(snapshot.status, STATUS_DEGRADED)
+        self.assertTrue(snapshot.ready)
+        self.assertTrue(any("gitea" in reason for reason in snapshot.readiness_reasons))
+
+    def test_unrun_required_probe_leaves_readiness_incomplete(self):
+        """Not probed is not the same as passing."""
+        probes = (
+            _probe("control_plane_db", STATUS_OK, kind="sqlite"),
+            _probe("repository", STATUS_SKIPPED, detail="offline", kind="git"),
+        )
+        snapshot = load_system_health(probes=probes, daemon_head="abc123")
+        self.assertFalse(snapshot.ready)
+        self.assertFalse(snapshot.readiness_complete)
+        self.assertEqual(snapshot.status, STATUS_DEGRADED)
+
+    def test_skipped_optional_probe_does_not_block_readiness(self):
+        probes = (
+            _probe("control_plane_db", STATUS_OK, kind="sqlite"),
+            _probe("repository", STATUS_OK, kind="git"),
+            _probe("gitea", STATUS_SKIPPED, required=False, kind="http"),
+        )
+        snapshot = load_system_health(probes=probes, daemon_head="abc123")
+        self.assertTrue(snapshot.ready)
+        self.assertTrue(snapshot.readiness_complete)
+
+
+class TestVersionAndUptime(CleanParityMixin, unittest.TestCase):
+    """AC2 — version and uptime present when knowable."""
+
+    def test_uptime_and_start_time_present(self):
+        snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="abc123")
+        self.assertGreaterEqual(snapshot.uptime_seconds, 0.0)
+        self.assertIn("T", snapshot.started_at)
+
+    def test_process_uptime_helper_matches_shape(self):
+        started_at, uptime = process_uptime()
+        self.assertIn("T", started_at)
+        self.assertGreaterEqual(uptime, 0.0)
+
+    def test_version_reports_python_and_schema_version(self):
+        probes = (
+            DependencyProbe(
+                name="control_plane_db",
+                kind="sqlite",
+                status=STATUS_OK,
+                detail="ok",
+                required=True,
+                latency_ms=1.0,
+                metadata={"schema_version": control_plane_db.SCHEMA_VERSION},
+            ),
+            _probe("repository", STATUS_OK, kind="git"),
+        )
+        snapshot = load_system_health(probes=probes, daemon_head="abc123")
+        self.assertEqual(
+            snapshot.version.control_plane_schema_version,
+            control_plane_db.SCHEMA_VERSION,
+        )
+        self.assertTrue(snapshot.version.python_version)
+
+    def test_version_known_flag_false_when_sha_unavailable(self):
+        with mock.patch("webui.system_health._git", return_value=None):
+            snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="abc")
+        self.assertIsNone(snapshot.version.git_sha)
+        self.assertFalse(snapshot.version.known)
+
+
+class TestStaleRuntime(unittest.TestCase):
+    """AC3 — stale runtime reflected without a false mutation-safe claim."""
+
+    def test_matching_commits_are_mutation_safe(self):
+        assessment = assess_stale_runtime(
+            Path("/tmp"),
+            daemon_head="aaa",
+            git_reader=lambda *args: "aaa",
+        )
+        self.assertFalse(assessment.stale)
+        self.assertTrue(assessment.determinable)
+        self.assertTrue(assessment.mutation_safe)
+
+    def test_diverged_commits_are_stale_and_not_mutation_safe(self):
+        reads = {"HEAD": "aaa", "@{upstream}": "bbb"}
+        assessment = assess_stale_runtime(
+            Path("/tmp"),
+            daemon_head="aaa",
+            git_reader=lambda *args: reads.get(args[-1]),
+        )
+        self.assertTrue(assessment.stale)
+        self.assertFalse(assessment.mutation_safe)
+        self.assertTrue(assessment.reasons)
+
+    def test_unknown_remote_is_not_mutation_safe(self):
+        """Indeterminate must never read as safe."""
+        reads = {"HEAD": "aaa", "@{upstream}": None}
+        assessment = assess_stale_runtime(
+            Path("/tmp"),
+            daemon_head="aaa",
+            git_reader=lambda *args: reads.get(args[-1]),
+        )
+        self.assertFalse(assessment.determinable)
+        self.assertFalse(assessment.mutation_safe)
+        self.assertFalse(assessment.stale)
+        self.assertTrue(
+            any("indeterminate" in reason for reason in assessment.reasons)
+        )
+
+    def test_unobservable_daemon_head_is_disclosed(self):
+        assessment = assess_stale_runtime(
+            Path("/tmp"),
+            git_reader=lambda *args: "aaa",
+        )
+        self.assertTrue(
+            any("not observable" in reason for reason in assessment.reasons)
+        )
+
+    def test_stale_runtime_degrades_overall_status(self):
+        reads = {"HEAD": "aaa", "@{upstream}": "bbb"}
+        # Pinned rather than inherited: this path uses the default git reader,
+        # so the assertion must hold whether or not the suite runs offline.
+        with mock.patch.dict(os.environ, {"WEBUI_TEST_OFFLINE": ""}), mock.patch(
+            "webui.system_health._git",
+            side_effect=lambda repo, *args: reads.get(args[-1]),
+        ):
+            snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="aaa")
+        self.assertTrue(snapshot.stale_runtime.stale)
+        self.assertFalse(snapshot.stale_runtime.mutation_safe)
+        self.assertEqual(snapshot.status, STATUS_DEGRADED)
+
+
+class TestControlPlaneDbProbe(unittest.TestCase):
+    """The required local dependency, probed read-only."""
+
+    def setUp(self):
+        self.tmp = tempfile.TemporaryDirectory()
+        self.addCleanup(self.tmp.cleanup)
+        self.db_path = str(Path(self.tmp.name) / "control-plane.db")
+
+    def _build_db(self, schema_version):
+        conn = sqlite3.connect(self.db_path)
+        conn.execute("CREATE TABLE schema_meta (key TEXT PRIMARY KEY, value TEXT)")
+        conn.execute("CREATE TABLE leases (lease_id TEXT PRIMARY KEY, status TEXT)")
+        conn.execute(
+            "INSERT INTO schema_meta(key, value) VALUES ('schema_version', ?)",
+            (str(schema_version),),
+        )
+        conn.execute("INSERT INTO leases(lease_id, status) VALUES ('l1', 'active')")
+        conn.commit()
+        conn.close()
+
+    def test_missing_database_is_down(self):
+        probe = probe_control_plane_db(str(Path(self.tmp.name) / "absent.db"))
+        self.assertEqual(probe.status, STATUS_DOWN)
+        self.assertTrue(probe.required)
+        self.assertIsNotNone(probe.latency_ms)
+
+    def test_matching_schema_is_ok(self):
+        self._build_db(control_plane_db.SCHEMA_VERSION)
+        probe = probe_control_plane_db(self.db_path)
+        self.assertEqual(probe.status, STATUS_OK)
+        self.assertEqual(
+            probe.metadata["schema_version"], control_plane_db.SCHEMA_VERSION
+        )
+        self.assertEqual(probe.metadata["active_leases"], 1)
+
+    def test_mismatched_schema_is_degraded(self):
+        self._build_db(control_plane_db.SCHEMA_VERSION + 99)
+        probe = probe_control_plane_db(self.db_path)
+        self.assertEqual(probe.status, STATUS_DEGRADED)
+
+    def test_probe_does_not_create_a_database(self):
+        """A health check must never initialise the substrate it inspects."""
+        absent = str(Path(self.tmp.name) / "never-created.db")
+        probe_control_plane_db(absent)
+        self.assertFalse(Path(absent).exists())
+
+    def test_unreadable_database_is_down_not_raised(self):
+        Path(self.db_path).write_text("this is not a sqlite database")
+        probe = probe_control_plane_db(self.db_path)
+        self.assertEqual(probe.status, STATUS_DOWN)
+
+
+class TestRedaction(unittest.TestCase):
+    """AC4 — redaction. No credential-shaped text crosses the boundary."""
+
+    def test_redacts_token_assignment(self):
+        cleaned = redact("failed with token=ghp_ABCDEFGHIJKLMNOPQRSTUVWXYZ012345")
+        self.assertNotIn("ghp_ABCDEFGHIJKLMNOPQRSTUVWXYZ012345", cleaned)
+        self.assertIn("[redacted]", cleaned)
+
+    def test_redacts_authorization_header_text(self):
+        cleaned = redact("Authorization: Bearer abcdefghijklmnopqrstuvwxyz123456")
+        self.assertNotIn("abcdefghijklmnopqrstuvwxyz123456", cleaned)
+
+    def test_redacts_long_opaque_strings(self):
+        cleaned = redact("value 0123456789abcdef0123456789abcdef here")
+        self.assertNotIn("0123456789abcdef0123456789abcdef", cleaned)
+
+    def test_url_userinfo_and_query_are_stripped(self):
+        cleaned = redact_url("https://user:[email protected]/api/v1?token=xyz")
+        self.assertNotIn("secretpass", cleaned)
+        self.assertNotIn("token=xyz", cleaned)
+        self.assertEqual(cleaned, "https://gitea.example.com/api/v1")
+
+    def test_url_inside_free_text_is_redacted(self):
+        cleaned = redact("GET https://u:[email protected]/x?token=abc failed")
+        self.assertNotIn("u:p@", cleaned)
+        self.assertNotIn("token=abc", cleaned)
+
+    def test_gitea_probe_failure_detail_is_redacted(self):
+        boom = RuntimeError(
+            "connection refused for https://user:[email protected]/api/v1/version"
+        )
+        with mock.patch("webui.system_health.get_auth_header", return_value="token x"), \
+                mock.patch("webui.system_health.api_request", side_effect=boom):
+            probe = probe_gitea("gitea.example.com")
+        self.assertEqual(probe.status, STATUS_DOWN)
+        self.assertNotIn("hunter2", probe.detail)
+        self.assertEqual(scan_text_for_client_secrets(probe.detail), [])
+
+    def test_credential_guard_refusal_is_a_status_not_a_crash(self):
+        with mock.patch(
+            "webui.system_health.get_auth_header",
+            side_effect=RuntimeError("daemon guard refused"),
+        ):
+            probe = probe_gitea("gitea.example.com")
+        self.assertEqual(probe.status, STATUS_DEGRADED)
+        self.assertFalse(probe.required)
+
+
+class TestNamespaceSummaries(unittest.TestCase):
+    """A web process cannot prove IDE namespace health, and must not claim to."""
+
+    def test_every_namespace_reports_unproven(self):
+        rows = namespace_summaries()
+        self.assertTrue(rows)
+        for row in rows:
+            with self.subTest(namespace=row["namespace"]):
+                self.assertEqual(row["status"], "unproven")
+                self.assertFalse(row["ide_namespace_proven"])
+                self.assertIn("client_namespace", row["reason"])
+
+
+class TestSystemHealthRoutes(CleanParityMixin, unittest.TestCase):
+    """The HTTP surface: versioned path, status codes, read-only guard."""
+
+    def setUp(self):
+        super().setUp()
+        clear_probe_cache()
+        self.addCleanup(clear_probe_cache)
+        self.client = TestClient(create_app())
+
+    def _patch_snapshot(self, probes, daemon_head="abc123"):
+        snapshot = load_system_health(probes=probes, daemon_head=daemon_head)
+        patcher = mock.patch(
+            "webui.app.load_system_health",
+            return_value=snapshot,
+        )
+        patcher.start()
+        self.addCleanup(patcher.stop)
+        return snapshot
+
+    def test_versioned_route_is_registered(self):
+        self.assertEqual(API_PATH, "/api/v1/system/health")
+        self._patch_snapshot(_ALL_HEALTHY)
+        response = self.client.get(API_PATH)
+        self.assertEqual(response.status_code, 200)
+
+    def test_healthy_payload_shape(self):
+        self._patch_snapshot(_ALL_HEALTHY)
+        data = self.client.get(API_PATH).json()
+        self.assertEqual(data["status"], STATUS_OK)
+        self.assertTrue(data["readiness"]["ready"])
+        self.assertTrue(data["readiness"]["complete"])
+        self.assertEqual(data["api"], API_PATH)
+        self.assertEqual(len(data["dependencies"]), 3)
+        for key in ("version", "process", "stale_runtime", "mcp_namespaces"):
+            self.assertIn(key, data)
+        self.assertIn("uptime_seconds", data["process"])
+        self.assertIn("mutation_safe", data["stale_runtime"])
+
+    def test_degraded_dependency_returns_503(self):
+        probes = (
+            _probe("control_plane_db", STATUS_DOWN, detail="missing", kind="sqlite"),
+            _probe("repository", STATUS_OK, kind="git"),
+        )
+        self._patch_snapshot(probes)
+        response = self.client.get(API_PATH)
+        self.assertEqual(response.status_code, 503)
+        data = response.json()
+        self.assertFalse(data["readiness"]["ready"])
+        self.assertTrue(data["readiness"]["reasons"])
+
+    def test_dependency_entries_expose_status_and_latency(self):
+        self._patch_snapshot(_ALL_HEALTHY)
+        data = self.client.get(API_PATH).json()
+        names = {entry["name"] for entry in data["dependencies"]}
+        self.assertEqual(names, {"control_plane_db", "repository", "gitea"})
+        for entry in data["dependencies"]:
+            with self.subTest(dependency=entry["name"]):
+                self.assertIn("status", entry)
+                self.assertIn("required", entry)
+                self.assertIn("latency_ms", entry)
+
+    def test_response_body_carries_no_client_secrets(self):
+        self._patch_snapshot(_ALL_HEALTHY)
+        body = self.client.get(API_PATH).text
+        self.assertEqual(scan_text_for_client_secrets(body), [])
+
+    def test_deep_flag_is_forwarded(self):
+        snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="abc")
+        with mock.patch(
+            "webui.app.load_system_health", return_value=snapshot
+        ) as loader:
+            self.client.get(f"{API_PATH}?deep=1")
+            loader.assert_called_once_with(deep=True)
+
+    def test_shallow_is_the_default(self):
+        snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="abc")
+        with mock.patch(
+            "webui.app.load_system_health", return_value=snapshot
+        ) as loader:
+            self.client.get(API_PATH)
+            loader.assert_called_once_with(deep=False)
+
+    def test_route_rejects_mutation_methods(self):
+        for method in ("POST", "PUT", "PATCH", "DELETE"):
+            with self.subTest(method=method):
+                response = self.client.request(method, API_PATH)
+                self.assertEqual(response.status_code, 405)
+                self.assertEqual(response.json()["error"], "read-only-mvp")
+
+    def test_default_shallow_call_skips_the_network_probe(self):
+        """The expensive probe must not run unless it was asked for."""
+        with mock.patch("webui.system_health.probe_gitea") as probe:
+            snapshot = load_system_health(deep=False)
+        probe.assert_not_called()
+        gitea = next(p for p in snapshot.dependencies if p.name == "gitea")
+        self.assertEqual(gitea.status, STATUS_SKIPPED)
+
+
+class TestHealthRouteBackwardCompatibility(unittest.TestCase):
+    """`/health` is expanded additively; MVP consumers must keep working."""
+
+    def setUp(self):
+        self.client = TestClient(create_app())
+
+    def test_mvp_keys_are_unchanged(self):
+        data = self.client.get("/health").json()
+        self.assertEqual(data["status"], "ok")
+        self.assertEqual(data["service"], "mcp-control-plane-webui")
+        self.assertEqual(data["mode"], "read-only-mvp")
+        self.assertIn("timestamp", data)
+        self.assertEqual(data["deployment"]["mode"], "internal-operator-console")
+
+    def test_health_points_at_the_versioned_api(self):
+        data = self.client.get("/health").json()
+        self.assertEqual(data["system_health_api"], API_PATH)
+        self.assertIn("uptime_seconds", data)
+        self.assertIn("started_at", data)
+
+    def test_health_runs_no_dependency_probe(self):
+        """Liveness must stay cheap: no probe, no snapshot assembly."""
+        with mock.patch("webui.app.load_system_health") as loader:
+            response = self.client.get("/health")
+        self.assertEqual(response.status_code, 200)
+        loader.assert_not_called()
+
+
+class TestSnapshotSerialisation(CleanParityMixin, unittest.TestCase):
+    def test_snapshot_dict_is_json_serialisable(self):
+        snapshot = load_system_health(probes=_ALL_HEALTHY, daemon_head="abc123")
+        encoded = json.dumps(snapshot_to_dict(snapshot))
+        self.assertIn("readiness", encoded)
+
+
+if __name__ == "__main__":
+    unittest.main()

webui/app.py

@@ -12,6 +12,7 @@ from starlette.routing import Route
 
 from webui.deployment_boundary import deployment_snapshot
 from webui.layout import render_page
+from webui.nav import NAV_GROUPS, STUB_PAGES
 from webui.project_registry import (
     ProjectRegistry,
     RegistryError,
@@ -45,6 +46,13 @@ from webui.worktree_scanner import load_hygiene_snapshot, snapshot_to_dict as wo
 from webui.worktree_views import render_worktrees_page
 from webui.runtime_health import load_runtime_snapshot, snapshot_to_dict as runtime_snapshot_to_dict
 from webui.runtime_views import render_runtime_page
+from webui.timeline import load_timeline, snapshot_to_dict as timeline_snapshot_to_dict
+from webui.system_health import (
+    API_PATH as SYSTEM_HEALTH_API_PATH,
+    load_system_health,
+    process_uptime,
+    snapshot_to_dict as system_health_to_dict,
+)
 
 _READ_ONLY_METHODS = frozenset({"GET", "HEAD", "OPTIONS"})
 _AUDIT_MUTATION_PATHS = frozenset({"/audit", "/api/audit"})
@@ -59,35 +67,100 @@ def _stub_page(title: str, description: str) -> HTMLResponse:
     return HTMLResponse(render_page(title=title, body_html=body))
 
 
+_LEGACY_PAGES = (
+    ("/queue", "Queue", "live PR and issue dashboard (#429)"),
+    ("/projects", "Projects", "registry and onboarding (#427)"),
+    ("/prompts", "Prompts", "canonical workflow prompt library (#428)"),
+    ("/runtime", "Runtime", "MCP health and stale-runtime detection (#430)"),
+    ("/audit", "Audit", "final-report paste and validator preview (#431)"),
+    ("/worktrees", "Worktrees", "branch hygiene dashboard (#432)"),
+    ("/leases", "Leases", "collision and lease visibility (#433)"),
+    ("/actions", "Actions", "gated write-action framework (#434)"),
+)
+
+
+def _render_home_nav_groups() -> str:
+    groups = []
+    for group in NAV_GROUPS:
+        items = "".join(
+            f'<li><a href="{item.href}">{item.label}</a>'
+            + ("" if item.status == "live" else " <span class=\"muted\">(stub)</span>")
+            + "</li>"
+            for item in group.items
+        )
+        groups.append(f"<h3>{group.label}</h3><ul>{items}</ul>")
+    return "".join(groups)
+
+
 async def home(_request: Request) -> HTMLResponse:
+    legacy = "".join(
+        f"<li><strong>{label}</strong> — {desc} "
+        f'(<a href="{href}">{href}</a>)</li>'
+        for href, label, desc in _LEGACY_PAGES
+    )
     body = (
         "<h2>Operator console</h2>"
-        "<p>Local entry point for MCP Control Plane operational views.</p>"
-        "<ul>"
-        "<li><strong>Queue</strong> — live PR and issue dashboard (#429)</li>"
-        "<li><strong>Projects</strong> — registry and onboarding (#427)</li>"
-        "<li><strong>Prompts</strong> — canonical workflow prompt library (#428)</li>"
-        "<li><strong>Runtime</strong> — MCP health and stale-runtime detection (#430)</li>"
-        "<li><strong>Audit</strong> — final-report paste and validator preview (#431)</li>"
-        "<li><strong>Worktrees</strong> — branch hygiene dashboard (#432)</li>"
-        "<li><strong>Leases</strong> — collision and lease visibility (#433)</li>"
-        "<li><strong>Actions</strong> — gated write-action framework (#434)</li>"
-        "</ul>"
+        "<p>Read-only home for the MCP Control Plane Phase 1 operator console. "
+        "Gitea, MCP capability gates, and canonical workflows remain the source "
+        "of truth; this console never mutates them.</p>"
+        "<h2>Phase 1 surfaces</h2>"
+        + _render_home_nav_groups()
+        + "<h2>MVP legacy pages</h2>"
+        "<ul>" + legacy + "</ul>"
     )
     return HTMLResponse(render_page(title="Home", body_html=body))
 
 
+async def phase_stub(request: Request) -> HTMLResponse:
+    """Graceful read-only placeholder for a not-yet-implemented Phase 1 surface."""
+    title, description = STUB_PAGES[request.url.path]
+    body = (
+        f"<h2>{title}</h2>"
+        f'<div class="stub"><p>{description}</p>'
+        "<p>Phase 1 shell placeholder — no write actions. Tracked under "
+        "epic #631.</p></div>"
+    )
+    return HTMLResponse(render_page(title=title, body_html=body))
+
+
 async def health(_request: Request) -> JSONResponse:
+    """Liveness only — deliberately cheap, runs no dependency probe (#634).
+
+    Every MVP key is retained so existing pollers keep working; the additions
+    are a pointer to the structured API and the in-memory process uptime.
+    Readiness lives at that API because answering it costs real probes.
+    """
     bind_host = _request.app.state.webui_bind_host
+    started_at, uptime_seconds = process_uptime()
     return JSONResponse({
         "status": "ok",
         "service": "mcp-control-plane-webui",
         "mode": "read-only-mvp",
         "timestamp": datetime.now(timezone.utc).isoformat(),
         "deployment": deployment_snapshot(bind_host=bind_host),
+        "started_at": started_at,
+        "uptime_seconds": uptime_seconds,
+        "system_health_api": SYSTEM_HEALTH_API_PATH,
     })
 
 
+def _truthy_flag(value: str | None) -> bool:
+    return (value or "").strip().lower() in {"1", "true", "yes", "on"}
+
+
+async def api_system_health(request: Request) -> JSONResponse:
+    """Structured read-only system health (#634).
+
+    `?deep=1` opts into the expensive network probe. The response status code
+    reflects readiness so automated checks can branch on it without parsing the
+    body: 200 when ready, 503 when a required dependency failed or never ran.
+    """
+    deep = _truthy_flag(request.query_params.get("deep"))
+    snapshot = load_system_health(deep=deep)
+    payload = system_health_to_dict(snapshot)
+    return JSONResponse(payload, status_code=200 if snapshot.ready else 503)
+
+
 async def queue(_request: Request) -> HTMLResponse:
     snapshot = load_queue_snapshot()
     return HTMLResponse(render_page(title="Queue", body_html=render_queue_page(snapshot)))
@@ -377,6 +450,104 @@ async def api_console_security_model(_request: Request) -> JSONResponse:
     })
 
 
+def _query_int(request: Request, key: str) -> int | None:
+    """Parse an optional integer query parameter; None when absent/invalid."""
+    raw = request.query_params.get(key)
+    if raw is None or not str(raw).strip():
+        return None
+    try:
+        return int(str(raw).strip())
+    except (TypeError, ValueError):
+        return None
+
+
+def _derive_remote(host: str) -> str:
+    """Map a Gitea host to its known short remote name (control-plane scope key)."""
+    text = (host or "").lower()
+    if "prgs" in text:
+        return "prgs"
+    if "dadeschools" in text:
+        return "dadeschools"
+    return text.split(".")[0] if text else ""
+
+
+def _timeline_comment_source(host: str, org: str, repo: str):
+    """Build a fail-soft CTH-comment fetcher for one repo, or None when offline.
+
+    Returns a callable ``(kind, number) -> list[comment]``. Credentials or
+    network failures raise inside the callable so ``load_timeline`` degrades the
+    handoff source rather than the whole timeline. Offline test mode yields no
+    live source so the handoff section reports ``not run``.
+    """
+    import os
+
+    from gitea_auth import api_fetch_page, get_auth_header, repo_api_url
+
+    offline = (os.environ.get("WEBUI_TEST_OFFLINE") or "").strip().lower() in {"1", "true", "yes"}
+    if offline:
+        return None
+    auth = get_auth_header(host)
+    if not auth:
+        return None
+
+    def _fetch(kind: str, number: int) -> list:
+        segment = "pulls" if kind == "pr" else "issues"
+        url = f"{repo_api_url(host, org, repo)}/{segment}/{int(number)}/comments"
+        comments: list = []
+        page = 1
+        while page <= 20:
+            raw, meta = api_fetch_page(url, auth, page=page, limit=50)
+            comments.extend(raw)
+            if bool(meta["is_final_page"]):
+                break
+            page += 1
+        return comments
+
+    return _fetch
+
+
+async def api_v1_timeline(request: Request) -> JSONResponse:
+    """Read-only workflow-event timeline (#637). Filter by issue/PR/session."""
+    from webui.queue_loader import _host_from_url  # host normalisation helper
+
+    registry, error = _load_project_registry()
+    if error is not None:
+        return JSONResponse(error.to_dict(), status_code=500)
+    project = registry.projects[0] if registry.projects else None
+
+    org = request.query_params.get("org") or (project.gitea_owner if project else "")
+    repo = request.query_params.get("repo") or (project.repo_name if project else "")
+    host = _host_from_url(project.remote_host) if project else ""
+    remote = request.query_params.get("remote") or _derive_remote(host)
+
+    if not (remote and org and repo):
+        return JSONResponse(
+            {
+                "error": "timeline_scope_unresolved",
+                "detail": "no project in registry and no remote/org/repo query params provided",
+            },
+            status_code=400,
+        )
+
+    comment_source = _timeline_comment_source(host, org, repo) if (host and org and repo) else None
+
+    snapshot = load_timeline(
+        remote=remote,
+        org=org,
+        repo=repo,
+        issue=_query_int(request, "issue"),
+        pr=_query_int(request, "pr"),
+        session=(request.query_params.get("session") or None),
+        limit=_query_int(request, "limit"),
+        offset=_query_int(request, "offset"),
+        comment_source=comment_source,
+    )
+    # A filter no surviving source can carry is refused, not answered empty:
+    # a 200 with zero events would tell the operator no such activity exists.
+    status_code = 200 if snapshot.ok else 422
+    return JSONResponse(timeline_snapshot_to_dict(snapshot), status_code=status_code)
+
+
 async def method_not_allowed(request: Request, _exc: Exception) -> Response:
     path = request.url.path
     if path in _AUDIT_MUTATION_PATHS and request.method == "POST":
@@ -399,6 +570,7 @@ def create_app(*, bind_host: str | None = None) -> Starlette:
         routes=[
             Route("/", home, methods=["GET"]),
             Route("/health", health, methods=["GET"]),
+            Route(SYSTEM_HEALTH_API_PATH, api_system_health, methods=["GET"]),
             Route("/queue", queue, methods=["GET"]),
             Route("/api/queue", api_queue, methods=["GET"]),
             Route("/projects", projects, methods=["GET"]),
@@ -415,6 +587,7 @@ def create_app(*, bind_host: str | None = None) -> Starlette:
             Route("/api/prompts", api_prompts, methods=["GET"]),
             Route("/runtime", runtime, methods=["GET"]),
             Route("/api/runtime", api_runtime, methods=["GET"]),
+            Route("/api/v1/timeline", api_v1_timeline, methods=["GET"]),
             Route("/audit", audit, methods=["GET", "POST"]),
             Route("/api/audit", api_audit, methods=["GET", "POST"]),
             Route("/worktrees", worktrees, methods=["GET"]),
@@ -438,6 +611,10 @@ def create_app(*, bind_host: str | None = None) -> Starlette:
                 api_console_security_model,
                 methods=["GET"],
             ),
+            *[
+                Route(path, phase_stub, methods=["GET"])
+                for path in STUB_PAGES
+            ],
         ],
         exception_handlers={405: method_not_allowed},
     )

webui/layout.py

@@ -2,28 +2,66 @@
 
 from __future__ import annotations
 
-NAV_ITEMS = (
-    ("/", "Home"),
-    ("/queue", "Queue"),
-    ("/projects", "Projects"),
-    ("/prompts", "Prompts"),
-    ("/runtime", "Runtime"),
-    ("/audit", "Audit"),
-    ("/worktrees", "Worktrees"),
-    ("/leases", "Leases"),
-    ("/actions", "Actions"),
-)
+import os
+
+from webui.nav import NAV_GROUPS
 
 MVP_NOTICE = (
     "Read-only MVP — Gitea, MCP tools, and canonical workflows remain the "
     "source of truth. No mutation endpoints."
 )
 
+# Canonical docs entry point surfaced from the shell header (#638).
+DOCS_URL = (
+    "https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/src/branch/"
+    "master/docs/webui-local-dev.md"
+)
+
+_LOCAL_HOSTS = frozenset({"", "127.0.0.1", "localhost", "::1"})
+
+
+def environment_label() -> str:
+    """Classify the serving environment as ``local`` or ``remote`` (#638).
+
+    Derived from the same ``WEBUI_HOST`` default the app binds to; loopback
+    hosts are ``local``, anything else is ``remote``. Read-only signal only.
+    """
+    host = (os.environ.get("WEBUI_HOST", "127.0.0.1") or "").strip().lower()
+    return "local" if host in _LOCAL_HOSTS else "remote"
+
+
+def _render_nav() -> str:
+    groups_html = []
+    for group in NAV_GROUPS:
+        links = "".join(
+            f'<a href="{item.href}"'
+            + (' class="nav-stub"' if item.status == "stub" else "")
+            + f'>{item.label}</a>'
+            for item in group.items
+        )
+        groups_html.append(
+            '<div class="nav-group">'
+            f'<span class="nav-group-label">{group.label}</span>'
+            f'<span class="nav-group-links">{links}</span>'
+            "</div>"
+        )
+    return "".join(groups_html)
+
+
+def _render_badges() -> str:
+    env = environment_label()
+    return (
+        '<div class="header-badges">'
+        f'<span class="badge env-badge env-{env}">env: {env}</span>'
+        '<span class="badge mode-badge">mode: read-only</span>'
+        f'<a class="badge docs-link" href="{DOCS_URL}">Docs</a>'
+        "</div>"
+    )
+
 
 def render_page(*, title: str, body_html: str, extra_head: str = "") -> str:
-    nav_links = "".join(
-        f'<a href="{href}">{label}</a>' for href, label in NAV_ITEMS
-    )
+    nav_links = _render_nav()
+    header_badges = _render_badges()
     return f"""<!DOCTYPE html>
 <html lang="en">
 <head>
@@ -53,21 +91,58 @@ def render_page(*, title: str, body_html: str, extra_head: str = "") -> str:
       padding: 0.75rem 1.25rem;
     }}
     header h1 {{
-      margin: 0 0 0.5rem;
+      margin: 0;
       font-size: 1.1rem;
       font-weight: 600;
     }}
+    .header-top {{
+      display: flex;
+      flex-wrap: wrap;
+      align-items: center;
+      justify-content: space-between;
+      gap: 0.5rem 1rem;
+      margin-bottom: 0.6rem;
+    }}
+    .header-badges {{ display: inline-flex; flex-wrap: wrap; gap: 0.4rem; }}
+    .env-badge.env-local {{ color: #8fd19e; border-color: #3d6b4a; }}
+    .env-badge.env-remote {{ color: #e0c27a; border-color: #6b5730; }}
+    .mode-badge {{ color: #9ec8f0; border-color: #3d5f7a; }}
+    a.docs-link {{
+      color: var(--accent);
+      border-color: var(--accent);
+      text-decoration: none;
+      text-transform: none;
+    }}
+    a.docs-link:hover {{ filter: brightness(1.12); }}
     nav {{
       display: flex;
       flex-wrap: wrap;
-      gap: 0.75rem 1rem;
+      gap: 0.5rem 1.25rem;
     }}
+    .nav-group {{
+      display: flex;
+      flex-direction: column;
+      gap: 0.15rem;
+    }}
+    .nav-group-label {{
+      font-size: 0.68rem;
+      text-transform: uppercase;
+      letter-spacing: 0.04em;
+      color: var(--muted);
+    }}
+    .nav-group-links {{ display: inline-flex; flex-wrap: wrap; gap: 0.6rem; }}
     nav a {{
       color: var(--accent);
       text-decoration: none;
       font-size: 0.9rem;
     }}
     nav a:hover {{ text-decoration: underline; }}
+    nav a.nav-stub {{ color: var(--muted); }}
+    nav a.nav-stub::after {{
+      content: " ·stub";
+      font-size: 0.7rem;
+      color: var(--muted);
+    }}
     main {{
       max-width: 52rem;
       margin: 0 auto;
@@ -166,7 +241,10 @@ def render_page(*, title: str, body_html: str, extra_head: str = "") -> str:
 </head>
 <body>
   <header>
-    <h1>MCP Control Plane</h1>
+    <div class="header-top">
+      <h1>MCP Control Plane</h1>
+      {header_badges}
+    </div>
     <nav>{nav_links}</nav>
   </header>
   <main>

webui/nav.py

@@ -0,0 +1,111 @@
+"""Navigation IA for the Phase 1 operator console shell (#638).
+
+Single source of truth for the console navigation so ``webui/layout.py`` and
+the ``webui/app.py`` route table stay aligned with epic #631. Read-only: every
+destination is a GET view or a Phase 1 placeholder. No mutation links.
+
+Nav groups follow the #631 Phase 1 information architecture: Health, Traffic,
+Runtime/Sessions, Projects, Inventory, Timeline, Policy (placeholder), and
+Insights (placeholder). Later-phase surfaces are declared as ``stub`` items and
+backed by ``STUB_PAGES`` so their nav links resolve to a graceful placeholder
+instead of a 404.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class NavItem:
+    """A single navigation destination.
+
+    ``status`` is ``"live"`` for implemented views and ``"stub"`` for Phase 1
+    placeholders whose backing view lands in a later child issue.
+    """
+
+    href: str
+    label: str
+    status: str = "live"
+
+
+@dataclass(frozen=True)
+class NavGroup:
+    label: str
+    items: tuple[NavItem, ...]
+
+
+NAV_GROUPS: tuple[NavGroup, ...] = (
+    NavGroup("Health", (
+        NavItem("/health", "Liveness"),
+    )),
+    NavGroup("Traffic", (
+        NavItem("/queue", "Queue"),
+        NavItem("/leases", "Leases"),
+        NavItem("/actions", "Actions"),
+    )),
+    NavGroup("Runtime/Sessions", (
+        NavItem("/runtime", "Runtime health"),
+        NavItem("/sessions", "Sessions", "stub"),
+    )),
+    NavGroup("Projects", (
+        NavItem("/projects", "Projects"),
+    )),
+    NavGroup("Inventory", (
+        NavItem("/inventory", "Inventory", "stub"),
+        NavItem("/worktrees", "Worktrees"),
+    )),
+    NavGroup("Timeline", (
+        NavItem("/timeline", "Timeline", "stub"),
+    )),
+    NavGroup("Policy", (
+        NavItem("/policy", "Policy", "stub"),
+        NavItem("/prompts", "Prompts"),
+    )),
+    NavGroup("Insights", (
+        NavItem("/insights", "Insights", "stub"),
+        NavItem("/audit", "Audit"),
+    )),
+)
+
+
+# Phase 1 placeholder destinations whose backing views land in later child
+# issues of epic #631. Each maps a path to (title, description). Routes are
+# registered so nav links resolve to a graceful, read-only stub page.
+STUB_PAGES: dict[str, tuple[str, str]] = {
+    "/sessions": (
+        "Sessions",
+        "Active session, capability, and role inventory. Backed by the unified "
+        "inventory API (#636) once it lands.",
+    ),
+    "/inventory": (
+        "Inventory",
+        "Unified sessions, leases, locks, namespaces, and worktree inventory. "
+        "Backed by the Phase 1 inventory API (#636).",
+    ),
+    "/timeline": (
+        "Timeline",
+        "Workflow event timeline across issues and PRs. A later Phase 1 surface.",
+    ),
+    "/policy": (
+        "Policy",
+        "Capability and role policy surface. Placeholder until a later phase.",
+    ),
+    "/insights": (
+        "Insights",
+        "Aggregate operational insights and trends. Placeholder until a later "
+        "phase.",
+    ),
+}
+
+
+def iter_nav_items():
+    """Yield every ``NavItem`` across all groups in declared order."""
+    for group in NAV_GROUPS:
+        for item in group.items:
+            yield item
+
+
+def nav_hrefs() -> tuple[str, ...]:
+    """Return every navigation href in declared order."""
+    return tuple(item.href for item in iter_nav_items())

webui/system_health.py

@@ -0,0 +1,682 @@
+"""Read-only system-health model for the operator console API (#634).
+
+`/health` answers liveness only. Operators automating readiness checks need a
+structured view of *why* the control plane is or is not usable: which
+dependencies answered, how long they took, what version of the code is running,
+and whether the runtime is stale relative to its remote.
+
+Three rules shape this module.
+
+* **Read-only.** Every probe opens its subject read-only. The control-plane
+  database is opened through a ``mode=ro`` URI so a health check can never
+  create or migrate a schema, and no probe writes, restarts, or reloads
+  anything — restart controls are Phase 2, and #630 forbids process-kill
+  recovery outright.
+* **Fail-soft.** A dependency that is unreachable is a *status*, not an
+  exception. Probes catch their own failures and report them as a degraded or
+  down entry carrying a reason.
+* **Never claim more than was proven.** Readiness is derived only from probes
+  that actually ran, ``mutation_safe`` stays false unless the parity commits are
+  known and equal, and an MCP namespace is reported unproven because a web
+  process cannot exercise the IDE-managed client path (#543).
+"""
+
+from __future__ import annotations
+
+import os
+import re
+import sqlite3
+import subprocess
+import time
+from dataclasses import dataclass
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Any, Callable
+from urllib.parse import urlsplit, urlunsplit
+
+import control_plane_db
+import mcp_namespace_health
+from gitea_auth import api_request, get_auth_header, gitea_url
+
+from webui.project_registry import load_registry
+
+SERVICE_NAME = "mcp-control-plane-webui"
+API_PATH = "/api/v1/system/health"
+
+STATUS_OK = "ok"
+STATUS_DEGRADED = "degraded"
+STATUS_DOWN = "down"
+STATUS_SKIPPED = "skipped"
+STATUS_UNPROVEN = "unproven"
+
+# Statuses that count as a healthy answer from a probe.
+_HEALTHY_STATUSES = frozenset({STATUS_OK})
+# Statuses meaning "this probe did not run", as opposed to "it ran and failed".
+_NOT_RUN_STATUSES = frozenset({STATUS_SKIPPED})
+
+_DEEP_PROBE_TTL_ENV = "WEBUI_HEALTH_PROBE_TTL_SECONDS"
+_DEFAULT_DEEP_PROBE_TTL = 15.0
+_GITEA_PROBE_TIMEOUT_SECONDS = 5.0
+
+_OFFLINE_ENV = "WEBUI_TEST_OFFLINE"
+
+# Credential-shaped material that must never reach the browser, mirroring the
+# forbidden client patterns in webui/deployment_boundary.py.
+_SECRET_RE = re.compile(
+    r"(?i)\b(token|password|passwd|secret|authorization|bearer)\b\s*[:=]?\s*\S+"
+)
+_LONG_OPAQUE_RE = re.compile(r"\b[A-Za-z0-9_\-]{32,}\b")
+
+# Captured once at import so uptime measures this process, not the request.
+_STARTED_AT = datetime.now(timezone.utc)
+_STARTED_MONOTONIC = time.monotonic()
+
+# TTL cache for the expensive (network) probe only.
+_deep_cache: dict[str, tuple[float, "DependencyProbe"]] = {}
+
+
+@dataclass(frozen=True)
+class DependencyProbe:
+    """One dependency check, fail-soft, with its own latency."""
+
+    name: str
+    kind: str
+    status: str
+    detail: str
+    required: bool
+    latency_ms: float | None = None
+    metadata: dict[str, Any] | None = None
+
+    @property
+    def healthy(self) -> bool:
+        return self.status in _HEALTHY_STATUSES
+
+    @property
+    def ran(self) -> bool:
+        return self.status not in _NOT_RUN_STATUSES
+
+
+@dataclass(frozen=True)
+class VersionInfo:
+    git_sha: str | None
+    git_describe: str | None
+    control_plane_schema_version: int | None
+    python_version: str
+    known: bool
+
+
+@dataclass(frozen=True)
+class StaleRuntime:
+    """Parity between the running code, the checkout, and the remote.
+
+    ``mutation_safe`` is deliberately conservative: unknown is not safe.
+    """
+
+    daemon_head: str | None
+    checkout_head: str | None
+    remote_head: str | None
+    stale: bool
+    determinable: bool
+    mutation_safe: bool
+    reasons: tuple[str, ...]
+
+
+@dataclass(frozen=True)
+class SystemHealthSnapshot:
+    status: str
+    ready: bool
+    readiness_complete: bool
+    readiness_reasons: tuple[str, ...]
+    service: str
+    mode: str
+    version: VersionInfo
+    started_at: str
+    uptime_seconds: float
+    timestamp: str
+    deep_probes_requested: bool
+    dependencies: tuple[DependencyProbe, ...]
+    mcp_namespaces: tuple[dict[str, Any], ...]
+    stale_runtime: StaleRuntime
+    probe_errors: tuple[str, ...] = ()
+
+
+def process_uptime() -> tuple[str, float]:
+    """Process start timestamp and uptime — in-memory, safe for `/health`."""
+    return _STARTED_AT.isoformat(), round(time.monotonic() - _STARTED_MONOTONIC, 3)
+
+
+def _offline() -> bool:
+    return (os.environ.get(_OFFLINE_ENV) or "").strip().lower() in {"1", "true", "yes"}
+
+
+def _repo_root() -> Path:
+    override = (os.environ.get("WEBUI_REPO_ROOT") or "").strip()
+    if override:
+        return Path(override).resolve()
+    return Path(__file__).resolve().parent.parent
+
+
+def _deep_probe_ttl() -> float:
+    raw = (os.environ.get(_DEEP_PROBE_TTL_ENV) or "").strip()
+    if not raw:
+        return _DEFAULT_DEEP_PROBE_TTL
+    try:
+        value = float(raw)
+    except ValueError:
+        return _DEFAULT_DEEP_PROBE_TTL
+    return value if value >= 0 else _DEFAULT_DEEP_PROBE_TTL
+
+
+def redact(text: str) -> str:
+    """Strip credential-shaped material from operator-visible probe text.
+
+    Probe details carry exception strings, and an exception raised by an HTTP
+    client can quote the request that failed. Redaction happens here, at the
+    boundary where those strings become part of a browser-bound payload.
+    """
+    if not text:
+        return ""
+    cleaned = _redact_urls(text)
+    cleaned = _SECRET_RE.sub(lambda m: f"{m.group(1)}=[redacted]", cleaned)
+    return _LONG_OPAQUE_RE.sub("[redacted]", cleaned)
+
+
+def _redact_urls(text: str) -> str:
+    return re.sub(r"https?://\S+", lambda m: redact_url(m.group(0)), text)
+
+
+def redact_url(url: str) -> str:
+    """Reduce a URL to scheme://host/path — no userinfo, no query, no fragment."""
+    try:
+        parts = urlsplit(url)
+    except ValueError:
+        return "[redacted-url]"
+    if not parts.scheme or not parts.hostname:
+        return "[redacted-url]"
+    netloc = parts.hostname
+    if parts.port:
+        netloc = f"{netloc}:{parts.port}"
+    return urlunsplit((parts.scheme, netloc, parts.path, "", ""))
+
+
+def _git(repo: Path, *args: str) -> str | None:
+    try:
+        completed = subprocess.run(
+            ["git", "-C", str(repo), *args],
+            capture_output=True,
+            text=True,
+            check=False,
+            timeout=10,
+        )
+    except (OSError, subprocess.SubprocessError):
+        return None
+    if completed.returncode != 0:
+        return None
+    return (completed.stdout or "").strip() or None
+
+
+def _load_version(repo: Path, *, schema_version: int | None) -> VersionInfo:
+    import platform
+
+    git_sha = None if _offline() else _git(repo, "rev-parse", "HEAD")
+    describe = None if _offline() else _git(repo, "describe", "--tags", "--always")
+    return VersionInfo(
+        git_sha=git_sha,
+        git_describe=describe,
+        control_plane_schema_version=schema_version,
+        python_version=platform.python_version(),
+        known=bool(git_sha),
+    )
+
+
+# ---------------------------------------------------------------------------
+# Dependency probes
+# ---------------------------------------------------------------------------
+
+
+def _elapsed_ms(started: float) -> float:
+    return round((time.monotonic() - started) * 1000, 3)
+
+
+def probe_control_plane_db(db_path: str | None = None) -> DependencyProbe:
+    """Read-only reachability check for the control-plane SQLite substrate.
+
+    Opened through a ``mode=ro`` URI on purpose: ``ControlPlaneDB.__init__``
+    creates directories and runs schema migrations, which a health check must
+    never do.
+    """
+    path = (db_path or control_plane_db.default_db_path()).strip()
+    started = time.monotonic()
+    metadata: dict[str, Any] = {"path": path}
+
+    def _result(status: str, detail: str) -> DependencyProbe:
+        return DependencyProbe(
+            name="control_plane_db",
+            kind="sqlite",
+            status=status,
+            detail=detail,
+            required=True,
+            latency_ms=_elapsed_ms(started),
+            metadata=metadata,
+        )
+
+    if not path or not os.path.exists(path):
+        return _result(STATUS_DOWN, "control-plane database file does not exist yet")
+    try:
+        conn = sqlite3.connect(f"file:{path}?mode=ro", uri=True, timeout=5)
+        try:
+            row = conn.execute(
+                "SELECT value FROM schema_meta WHERE key = 'schema_version'"
+            ).fetchone()
+            leases = conn.execute(
+                "SELECT COUNT(*) FROM leases WHERE status = 'active'"
+            ).fetchone()
+        finally:
+            conn.close()
+    except sqlite3.Error as exc:
+        return _result(STATUS_DOWN, redact(f"control-plane database unreadable: {exc}"))
+
+    schema_version = int(row[0]) if row and str(row[0]).isdigit() else None
+    metadata["schema_version"] = schema_version
+    metadata["active_leases"] = int(leases[0]) if leases else None
+    if schema_version is None:
+        return _result(
+            STATUS_DEGRADED, "control-plane database has no recorded schema version"
+        )
+    if schema_version != control_plane_db.SCHEMA_VERSION:
+        return _result(
+            STATUS_DEGRADED,
+            f"control-plane schema version {schema_version} does not match the "
+            f"version this code expects ({control_plane_db.SCHEMA_VERSION})",
+        )
+    return _result(STATUS_OK, f"schema v{schema_version} readable")
+
+
+def probe_repository(repo: Path) -> DependencyProbe:
+    """Local checkout reachability — required, cheap, no network."""
+    started = time.monotonic()
+    metadata: dict[str, Any] = {"repo_root": str(repo)}
+    if _offline():
+        return DependencyProbe(
+            name="repository",
+            kind="git",
+            status=STATUS_SKIPPED,
+            detail=f"{_OFFLINE_ENV} is set; git probe skipped",
+            required=True,
+            latency_ms=_elapsed_ms(started),
+            metadata=metadata,
+        )
+    head = _git(repo, "rev-parse", "HEAD")
+    if not head:
+        return DependencyProbe(
+            name="repository",
+            kind="git",
+            status=STATUS_DOWN,
+            detail=f"HEAD could not be read at {repo}",
+            required=True,
+            latency_ms=_elapsed_ms(started),
+            metadata=metadata,
+        )
+    branch = _git(repo, "rev-parse", "--abbrev-ref", "HEAD")
+    metadata["head"] = head
+    metadata["branch"] = branch
+    return DependencyProbe(
+        name="repository",
+        kind="git",
+        status=STATUS_OK,
+        detail=f"checkout readable at {branch or 'detached HEAD'}",
+        required=True,
+        latency_ms=_elapsed_ms(started),
+        metadata=metadata,
+    )
+
+
+def probe_gitea(host: str) -> DependencyProbe:
+    """Live Gitea reachability. Expensive (network), so opt-in via ``deep``.
+
+    Optional by design: the console stays useful for local inventory when the
+    remote is unreachable, so a failure here degrades status without claiming
+    the process itself is unready.
+    """
+    started = time.monotonic()
+    metadata: dict[str, Any] = {"host": host}
+
+    def _failure(status: str, detail: str) -> DependencyProbe:
+        return DependencyProbe(
+            name="gitea",
+            kind="http",
+            status=status,
+            detail=detail,
+            required=False,
+            latency_ms=_elapsed_ms(started),
+            metadata=metadata,
+        )
+
+    if not host:
+        return _failure(STATUS_DEGRADED, "no Gitea host is configured in the registry")
+    try:
+        auth = get_auth_header(host)
+    except Exception as exc:  # noqa: BLE001 — credential guards are a status here
+        return _failure(STATUS_DEGRADED, redact(f"credential lookup refused: {exc}"))
+    if not auth:
+        return _failure(STATUS_DEGRADED, f"no credentials available for {host}")
+
+    url = gitea_url(host, "/api/v1/version")
+    metadata["endpoint"] = redact_url(url)
+    try:
+        data = api_request("GET", url, auth, timeout=_GITEA_PROBE_TIMEOUT_SECONDS)
+    except Exception as exc:  # noqa: BLE001 — a down dependency is a status
+        return _failure(STATUS_DOWN, redact(f"Gitea probe failed: {exc}"))
+
+    if isinstance(data, dict) and data.get("version"):
+        metadata["gitea_version"] = str(data["version"])
+    return DependencyProbe(
+        name="gitea",
+        kind="http",
+        status=STATUS_OK,
+        detail=f"{host} reachable",
+        required=False,
+        latency_ms=_elapsed_ms(started),
+        metadata=metadata,
+    )
+
+
+def _skipped_gitea(host: str) -> DependencyProbe:
+    return DependencyProbe(
+        name="gitea",
+        kind="http",
+        status=STATUS_SKIPPED,
+        detail="network probe not requested; call with ?deep=1 to run it",
+        required=False,
+        latency_ms=None,
+        metadata={"host": host},
+    )
+
+
+def namespace_summaries() -> tuple[dict[str, Any], ...]:
+    """Declared MCP namespaces, each honestly reported as unproven.
+
+    The web process runs outside the IDE-managed MCP client, so it cannot
+    invoke a namespace tool. Per #543 only a ``client_namespace`` probe proves
+    that path, and inventing a healthy verdict here is exactly the false claim
+    the mutation gates exist to prevent.
+    """
+    rows: list[dict[str, Any]] = []
+    for namespace, required_tool in sorted(
+        mcp_namespace_health.REQUIRED_NAMESPACE_TOOLS.items()
+    ):
+        classification = mcp_namespace_health.classify_namespace_probe(
+            namespace,
+            required_tool=required_tool,
+            probe_result=None,
+            probe_source=mcp_namespace_health.PROBE_SOURCE_UNKNOWN,
+        )
+        rows.append(
+            {
+                "namespace": namespace,
+                "required_tool": required_tool,
+                "status": STATUS_UNPROVEN,
+                "ide_namespace_proven": bool(classification.get("ide_namespace_proven")),
+                "reason": (
+                    "the web console cannot invoke the IDE-managed MCP client; "
+                    "namespace health must be proven with a client_namespace "
+                    "probe (#543)"
+                ),
+                "error_type": classification.get("error_type"),
+            }
+        )
+    return tuple(rows)
+
+
+def assess_stale_runtime(
+    repo: Path,
+    *,
+    daemon_head: str | None = None,
+    git_reader: Callable[..., str | None] | None = None,
+) -> StaleRuntime:
+    """Three-way parity view: running code, local checkout, remote-tracking ref.
+
+    ``mutation_safe`` requires all three to be known and equal. Anything less —
+    including "the remote ref was never fetched" — is reported as not safe with
+    a reason, so an operator never reads an unproven green.
+    """
+    reader = git_reader or (lambda *args: _git(repo, *args))
+    reasons: list[str] = []
+    # The offline switch suppresses real subprocess calls; an explicitly
+    # injected reader is already a substitute for them and is always used.
+    offline = _offline() and git_reader is None
+
+    checkout_head = None if offline else reader("rev-parse", "HEAD")
+    remote_head = None if offline else reader("rev-parse", "@{upstream}")
+    if offline:
+        reasons.append(f"{_OFFLINE_ENV} is set; parity commits were not read")
+    else:
+        if checkout_head is None:
+            reasons.append("local checkout HEAD could not be read")
+        if remote_head is None:
+            reasons.append(
+                "no remote-tracking commit is known for the current branch; "
+                "remote staleness is indeterminate (no fetch is performed here)"
+            )
+
+    effective_daemon = daemon_head if daemon_head is not None else checkout_head
+    if daemon_head is None:
+        reasons.append(
+            "the running MCP daemon's startup commit is not observable from the "
+            "web process; the checkout commit is reported in its place"
+        )
+
+    determinable = bool(checkout_head and remote_head and effective_daemon)
+    stale = bool(
+        determinable and len({checkout_head, remote_head, effective_daemon}) > 1
+    )
+    if stale:
+        reasons.append(
+            "runtime, checkout, and remote commits disagree; restart the MCP "
+            "server after updating the checkout before trusting capability gates"
+        )
+
+    return StaleRuntime(
+        daemon_head=effective_daemon,
+        checkout_head=checkout_head,
+        remote_head=remote_head,
+        stale=stale,
+        determinable=determinable,
+        mutation_safe=bool(determinable and not stale),
+        reasons=tuple(reasons),
+    )
+
+
+# ---------------------------------------------------------------------------
+# Snapshot assembly
+# ---------------------------------------------------------------------------
+
+
+def _default_host() -> str:
+    registry = load_registry()
+    if not registry.projects:
+        return ""
+    raw = registry.projects[0].remote_host
+    parts = urlsplit(raw.strip())
+    return parts.netloc or raw.strip().rstrip("/")
+
+
+def _aggregate(
+    probes: tuple[DependencyProbe, ...],
+) -> tuple[str, bool, bool, tuple[str, ...]]:
+    """Fold probe results into overall status and readiness.
+
+    Required probes drive readiness; optional probes can only degrade status.
+    A probe that did not run leaves readiness incomplete rather than passing.
+    """
+    reasons: list[str] = []
+    required = [probe for probe in probes if probe.required]
+    unrun_required = [probe for probe in required if not probe.ran]
+    failed_required = [probe for probe in required if probe.ran and not probe.healthy]
+    failed_optional = [
+        probe
+        for probe in probes
+        if not probe.required and probe.ran and not probe.healthy
+    ]
+
+    for probe in unrun_required:
+        reasons.append(
+            f"required dependency '{probe.name}' was not probed: {probe.detail}"
+        )
+    for probe in failed_required:
+        reasons.append(
+            f"required dependency '{probe.name}' is {probe.status}: {probe.detail}"
+        )
+    for probe in failed_optional:
+        reasons.append(
+            f"optional dependency '{probe.name}' is {probe.status}: {probe.detail}"
+        )
+
+    readiness_complete = not unrun_required
+    ready = readiness_complete and not failed_required
+
+    if any(probe.status == STATUS_DOWN for probe in failed_required):
+        status = STATUS_DOWN
+    elif failed_required or failed_optional or unrun_required:
+        status = STATUS_DEGRADED
+    else:
+        status = STATUS_OK
+    return status, ready, readiness_complete, tuple(reasons)
+
+
+def load_system_health(
+    *,
+    deep: bool = False,
+    host: str | None = None,
+    probes: tuple[DependencyProbe, ...] | None = None,
+    daemon_head: str | None = None,
+    use_cache: bool = True,
+) -> SystemHealthSnapshot:
+    """Assemble the read-only system-health snapshot.
+
+    ``deep=True`` adds the network probe against Gitea; its result is cached for
+    a short TTL so repeated dashboard polls do not amplify into remote load.
+    """
+    repo = _repo_root()
+    probe_errors: list[str] = []
+
+    if probes is None:
+        collected: list[DependencyProbe] = []
+        for probe_fn in (
+            lambda: probe_control_plane_db(),
+            lambda: probe_repository(repo),
+        ):
+            try:
+                collected.append(probe_fn())
+            except Exception as exc:  # noqa: BLE001 — a probe must not 500 the API
+                probe_errors.append(redact(f"probe raised: {exc}"))
+        resolved_host = host if host is not None else _default_host()
+        if deep and not _offline():
+            collected.append(_cached_gitea_probe(resolved_host, use_cache=use_cache))
+        else:
+            collected.append(_skipped_gitea(resolved_host))
+        probes = tuple(collected)
+
+    status, ready, readiness_complete, reasons = _aggregate(probes)
+    stale = assess_stale_runtime(repo, daemon_head=daemon_head)
+    if stale.stale:
+        if status == STATUS_OK:
+            status = STATUS_DEGRADED
+        reasons = reasons + (
+            "runtime is stale relative to its remote-tracking commit",
+        )
+
+    db_probe = next((p for p in probes if p.name == "control_plane_db"), None)
+    schema_version = None
+    if db_probe and db_probe.metadata:
+        schema_version = db_probe.metadata.get("schema_version")
+
+    return SystemHealthSnapshot(
+        status=status,
+        ready=ready,
+        readiness_complete=readiness_complete,
+        readiness_reasons=reasons,
+        service=SERVICE_NAME,
+        mode="read-only",
+        version=_load_version(repo, schema_version=schema_version),
+        started_at=_STARTED_AT.isoformat(),
+        uptime_seconds=round(time.monotonic() - _STARTED_MONOTONIC, 3),
+        timestamp=datetime.now(timezone.utc).isoformat(),
+        deep_probes_requested=deep,
+        dependencies=probes,
+        mcp_namespaces=namespace_summaries(),
+        stale_runtime=stale,
+        probe_errors=tuple(probe_errors),
+    )
+
+
+def _cached_gitea_probe(host: str, *, use_cache: bool = True) -> DependencyProbe:
+    ttl = _deep_probe_ttl()
+    now = time.monotonic()
+    if use_cache and ttl > 0:
+        cached = _deep_cache.get(host)
+        if cached and (now - cached[0]) < ttl:
+            return cached[1]
+    probe = probe_gitea(host)
+    if use_cache and ttl > 0:
+        _deep_cache[host] = (now, probe)
+    return probe
+
+
+def clear_probe_cache() -> None:
+    """Drop cached deep-probe results (tests and operator-forced refresh)."""
+    _deep_cache.clear()
+
+
+def probe_to_dict(probe: DependencyProbe) -> dict[str, Any]:
+    return {
+        "name": probe.name,
+        "kind": probe.kind,
+        "status": probe.status,
+        "detail": probe.detail,
+        "required": probe.required,
+        "healthy": probe.healthy,
+        "latency_ms": probe.latency_ms,
+        "metadata": dict(probe.metadata or {}),
+    }
+
+
+def snapshot_to_dict(snapshot: SystemHealthSnapshot) -> dict[str, Any]:
+    return {
+        "status": snapshot.status,
+        "service": snapshot.service,
+        "mode": snapshot.mode,
+        "api": API_PATH,
+        "timestamp": snapshot.timestamp,
+        "readiness": {
+            "ready": snapshot.ready,
+            "complete": snapshot.readiness_complete,
+            "reasons": list(snapshot.readiness_reasons),
+        },
+        "version": {
+            "git_sha": snapshot.version.git_sha,
+            "git_describe": snapshot.version.git_describe,
+            "control_plane_schema_version": (
+                snapshot.version.control_plane_schema_version
+            ),
+            "python_version": snapshot.version.python_version,
+            "known": snapshot.version.known,
+        },
+        "process": {
+            "started_at": snapshot.started_at,
+            "uptime_seconds": snapshot.uptime_seconds,
+        },
+        "deep_probes_requested": snapshot.deep_probes_requested,
+        "dependencies": [probe_to_dict(probe) for probe in snapshot.dependencies],
+        "mcp_namespaces": [dict(row) for row in snapshot.mcp_namespaces],
+        "stale_runtime": {
+            "daemon_head": snapshot.stale_runtime.daemon_head,
+            "checkout_head": snapshot.stale_runtime.checkout_head,
+            "remote_head": snapshot.stale_runtime.remote_head,
+            "stale": snapshot.stale_runtime.stale,
+            "determinable": snapshot.stale_runtime.determinable,
+            "mutation_safe": snapshot.stale_runtime.mutation_safe,
+            "reasons": list(snapshot.stale_runtime.reasons),
+        },
+        "probe_errors": list(snapshot.probe_errors),
+    }

webui/timeline.py

@@ -0,0 +1,906 @@
+"""Workflow-event and conversation timeline model (#637, Phase 1).
+
+Operators cannot browse a unified timeline of workflow events, decisions,
+tool calls, and handoffs: the evidence is scattered across control-plane
+events, Gitea canonical handoff comments, and local logs. This module defines
+one durable, versioned event schema and per-source adapters that normalise
+those scattered records into a single ``WorkflowEvent`` stream, plus a
+read-only query layer (filter by issue / PR / session, stable ordering,
+pagination) that the ``/api/v1/timeline`` route serves.
+
+Design rules honoured here:
+
+- **Read-only.** Sources are read; nothing is mutated. The control-plane
+  database is opened through a ``mode=ro`` URI so a missing or unwritable DB
+  degrades to a reason instead of creating directories or running migrations.
+- **Fail-soft per source.** An unavailable source degrades to a status with a
+  reason rather than raising, and a source that could not run is never
+  rendered as an empty-and-healthy timeline.
+- **Answerable filters only.** Each source declares which filter dimensions it
+  can actually answer. A filter dimension no source that ran can carry is
+  refused with an explicit reason rather than silently matching nothing: an
+  empty page from an unanswerable filter reads to an operator as "no such
+  activity", which is a different — and false — statement.
+- **Redaction at the boundary, fail closed.** Every free-text field (event
+  messages, redacted tool arguments, decision/proof text) is run through the
+  console redaction policy before it leaves this module, and *before* any
+  structured value is derived from it — evidence references are extracted from
+  redacted text, then independently revalidated before serialization. An
+  unredactable value becomes the placeholder, and a value that cannot be proven
+  safe is dropped — an unredacted payload is never emitted, and a generation
+  error never drops raw data to a caller or a log.
+- **Stable ordering.** Events sort by ``(timestamp, source_rank, event_key)``
+  with a deterministic tiebreak, so pagination is stable across calls and
+  events with equal or missing timestamps keep a fixed order.
+
+Non-goals (from the issue): no full chat replay, no mutation of historical
+events, no unredacted tool-argument storage.
+"""
+
+from __future__ import annotations
+
+import re
+import sqlite3
+from dataclasses import dataclass, replace
+from datetime import datetime, timezone
+from typing import Any, Callable, Iterable
+
+import control_plane_db
+from webui import console_redaction
+
+# The schema is versioned so consumers can branch on shape. Bump on any
+# breaking change to WorkflowEvent's serialized form.
+TIMELINE_SCHEMA_VERSION = 1
+
+# Known event sources and their deterministic ordering rank. When two events
+# carry the same timestamp, the source rank breaks the tie before the
+# per-source event key, so a control-plane event and a handoff comment minted
+# in the same second always sort in a fixed order.
+SOURCE_CONTROL_PLANE = "control_plane"
+SOURCE_GITEA_HANDOFF = "gitea_handoff"
+_SOURCE_RANK = {
+    SOURCE_CONTROL_PLANE: 0,
+    SOURCE_GITEA_HANDOFF: 1,
+}
+
+# The filter dimensions the query layer accepts.
+FILTER_ISSUE = "issue"
+FILTER_PR = "pr"
+FILTER_SESSION = "session"
+
+# Which dimensions each source can actually answer. This is a property of the
+# underlying records, not of the query code: the control-plane ``events`` table
+# is (event_id, work_item_id, event_type, message, created_at) and carries no
+# session identity at all, so no control-plane event can ever match a session
+# filter. A CTH handoff comment can declare its session as a field, so the
+# handoff source answers all three. Filtering on a dimension the surviving
+# sources cannot carry is refused in ``load_timeline`` rather than answered
+# with an empty page.
+_SOURCE_FILTER_SUPPORT: dict[str, tuple[str, ...]] = {
+    SOURCE_CONTROL_PLANE: (FILTER_ISSUE, FILTER_PR),
+    SOURCE_GITEA_HANDOFF: (FILTER_ISSUE, FILTER_PR, FILTER_SESSION),
+}
+
+# Why a source cannot answer a dimension, for the refusal reason an operator reads.
+_SOURCE_FILTER_LIMITS: dict[tuple[str, str], str] = {
+    (SOURCE_CONTROL_PLANE, FILTER_SESSION): (
+        "control-plane events carry no session identity "
+        "(the events table has no session column)"
+    ),
+}
+
+# A timestamp far in the future so events with no parseable timestamp sort
+# last (after everything real) instead of first, without raising.
+_MISSING_TS_SORT = "9999-12-31T23:59:59Z"
+
+
+def _parse_ts(value: str | None) -> str | None:
+    """Normalise a timestamp to ``...Z`` UTC, or None when unparseable."""
+    if not value:
+        return None
+    text = str(value).strip()
+    if not text:
+        return None
+    candidate = text[:-1] + "+00:00" if text.endswith("Z") else text
+    try:
+        parsed = datetime.fromisoformat(candidate)
+    except ValueError:
+        return None
+    if parsed.tzinfo is None:
+        parsed = parsed.replace(tzinfo=timezone.utc)
+    return parsed.astimezone(timezone.utc).replace(microsecond=0).isoformat().replace("+00:00", "Z")
+
+
+def _redact(value: Any) -> Any:
+    """Redact a single free-text field, failing closed to the placeholder."""
+    if value is None:
+        return None
+    return console_redaction.redact_text(str(value))
+
+
+@dataclass(frozen=True)
+class WorkflowEvent:
+    """One normalised timeline event.
+
+    Every field is optional except ``source``/``event_type``/``event_key``
+    because sources carry different subsets. The class is frozen so an adapted
+    event is an immutable record; a consumer that needs a variant builds a new
+    one rather than mutating history.
+    """
+
+    source: str
+    event_type: str
+    event_key: str
+    timestamp: str | None = None
+    actor: str | None = None
+    role: str | None = None
+    issue_number: int | None = None
+    pr_number: int | None = None
+    session_id: str | None = None
+    tool_name: str | None = None
+    decision: str | None = None
+    message: str | None = None
+    correlation_id: str | None = None
+    evidence_refs: tuple[str, ...] = ()
+    sensitive: bool = False
+
+    def sort_key(self) -> tuple[str, int, str]:
+        return (
+            self.timestamp or _MISSING_TS_SORT,
+            _SOURCE_RANK.get(self.source, 99),
+            self.event_key,
+        )
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "source": self.source,
+            "event_type": self.event_type,
+            "event_key": self.event_key,
+            "timestamp": self.timestamp,
+            "actor": self.actor,
+            "role": self.role,
+            "issue_number": self.issue_number,
+            "pr_number": self.pr_number,
+            "session_id": self.session_id,
+            "tool_name": self.tool_name,
+            "decision": self.decision,
+            "message": self.message,
+            "correlation_id": self.correlation_id,
+            "evidence_refs": list(self.evidence_refs),
+            "sensitive": self.sensitive,
+        }
+
+
+# --------------------------------------------------------------------------- #
+# Adapters — pure functions from a source's raw records to WorkflowEvents.     #
+# Each is total: a malformed record is skipped, never raised on.               #
+# --------------------------------------------------------------------------- #
+
+# Event types whose payload is treated as sensitive and always redaction-hard
+# (they can carry lease/session provenance or tool arguments).
+_SENSITIVE_EVENT_HINTS = ("lease", "capability", "token", "auth", "secret")
+
+# Reference tokens (issue/PR/comment ids) and SHAs parsed out of proof text.
+_EVIDENCE_REF_RE = re.compile(r"(?:#|PR\s*#?|issue\s*#?|comment\s*#?)(\d+)", re.IGNORECASE)
+
+# A commit reference is only recognised when the text *declares* it as one.
+# A bare lowercase hex run is not evidence of anything: at 40 characters it is
+# exactly the shape of a Gitea personal access token, and at 7 it also matches
+# ordinary words such as "defaced". Requiring an anchoring keyword keeps real
+# references ("commit abc1234", "at head a209756...", "base caaae9b6") usable
+# while refusing to lift an undeclared secret-shaped run out of free text.
+_SHA_RE = re.compile(
+    r"(?i:\b(?:commit|sha|head|base|parent|revision|rev|merge[- ]base)\b[\s:=@#]*)"
+    r"([0-9a-f]{7,40})\b"
+)
+
+# Shapes a serialized evidence reference is allowed to take. Anything else is
+# dropped rather than emitted.
+_REF_ISSUE_SHAPE = re.compile(r"^#[0-9]{1,9}$")
+_REF_SHA_SHAPE = re.compile(r"^[0-9a-f]{7,40}$")
+
+# A long undelimited hex run with no declaring context is treated as credential
+# material wherever it appears, never as an identifier.
+_BARE_SECRET_SHAPE = re.compile(r"^[0-9a-f]{32,}$")
+
+# An event type reads like an identifier, but a stored one is externally
+# influenced: any producer that writes the control-plane ``events`` table
+# chooses the string. It reaches ``to_dict`` verbatim, so it is validated here
+# rather than trusted because of where it came from.
+_CP_EVENT_TYPE_SHAPE = re.compile(r"^[A-Za-z][A-Za-z0-9._:+-]{0,63}$")
+
+# Emitted in place of a value that cannot be proven safe. Deliberately not a
+# plausible workflow type: an unsafe value is refused, never quietly rewritten
+# into a different valid-looking one that would misdescribe the record.
+UNSAFE_EVENT_TYPE = "unsafe:redacted"
+
+# Emitted for a CTH heading that is not a declared member of ``CTH_TYPES``. The
+# contract is enforced on write (``format_cth_body``) and on assess; the read
+# path the timeline uses enforces it too rather than assuming it was.
+UNKNOWN_HANDOFF_EVENT_TYPE = "handoff:unrecognized"
+
+# A source record id is a plain integer in both sources it comes from: the
+# control-plane ``events`` primary key and a Gitea comment id. ``event_key`` is
+# serialized verbatim and is the pagination tiebreak, so anything else is
+# refused rather than interpolated into it.
+_RECORD_ID_SHAPE = re.compile(r"^[0-9]{1,19}$")
+
+
+def _kind_to_numbers(kind: str | None, number: int | None) -> tuple[int | None, int | None]:
+    """Map a control-plane work-item (kind, number) to (issue_no, pr_no)."""
+    if number is None:
+        return (None, None)
+    if kind == "pr":
+        return (None, int(number))
+    if kind == "issue":
+        return (int(number), None)
+    return (None, None)
+
+
+def _correlation_for(kind: str | None, number: int | None) -> str | None:
+    if number is None or kind not in ("issue", "pr"):
+        return None
+    return f"{kind}#{number}"
+
+
+def _extract_evidence_refs(*texts: str | None) -> tuple[str, ...]:
+    """Extract issue/PR and declared-commit references from **redacted** text.
+
+    Callers must pass text that has already been through :func:`_redact`; this
+    function derives a structured field from its input, so extracting ahead of
+    redaction would republish whatever redaction was about to remove. Every
+    reference is revalidated by :func:`_validated_evidence_refs` before it is
+    serialized.
+    """
+    refs: list[str] = []
+    for text in texts:
+        if not text:
+            continue
+        for match in _EVIDENCE_REF_RE.finditer(text):
+            token = f"#{match.group(1)}"
+            if token not in refs:
+                refs.append(token)
+        for match in _SHA_RE.finditer(text):
+            token = match.group(1)
+            if token not in refs:
+                refs.append(token)
+    return tuple(refs)
+
+
+def _validated_evidence_refs(refs: Iterable[str]) -> tuple[tuple[str, ...], bool]:
+    """Independently revalidate references immediately before serialization.
+
+    Extraction is not trusted on its own. A reference survives only when it has
+    a known reference shape and is unchanged by a second redaction pass — a
+    value the redaction policy would alter is credential material that must not
+    be emitted as a structured field. A full 40-character SHA stays usable
+    because extraction only accepts a hex run the source text explicitly
+    declared as a commit. Returns ``(safe_refs, dropped_any)``; ``dropped_any``
+    marks the event sensitive so the drop is visible rather than silent.
+    """
+    safe: list[str] = []
+    dropped = False
+    for ref in refs or ():
+        try:
+            token = str(ref).strip()
+            if not token:
+                continue
+            recognised = bool(_REF_ISSUE_SHAPE.match(token) or _REF_SHA_SHAPE.match(token))
+            if not recognised:
+                dropped = True
+                continue
+            if _redact(token) != token:
+                dropped = True
+                continue
+            if token not in safe:
+                safe.append(token)
+        except Exception:
+            # Fail closed: a reference that cannot be proven safe is dropped.
+            dropped = True
+            continue
+    return (tuple(safe), dropped)
+
+
+def _safe_session_id(value: Any) -> str | None:
+    """Return a session identifier only when it is safe to emit.
+
+    The value is authoritative source data — a session the record names for
+    itself — but it is still free text. It is dropped when redaction alters it
+    or when it is a bare secret-shaped hex run, so a credential parked in a
+    session field can never reach the payload or be echoed back by a filter.
+    """
+    if value is None:
+        return None
+    text = str(value).strip()
+    if not text:
+        return None
+    if _BARE_SECRET_SHAPE.match(text):
+        return None
+    return text if _redact(text) == text else None
+
+
+def _safe_record_id(value: Any) -> str | None:
+    """Return a source record id only when it is a plain numeric identifier.
+
+    ``event_key`` is serialized verbatim and is the deterministic pagination
+    tiebreak, so an id is interpolated into it only when it has the shape both
+    real sources actually produce. A record whose identity cannot be trusted is
+    refused by the caller rather than keyed on.
+    """
+    if value is None or isinstance(value, bool):
+        return None
+    if isinstance(value, int):
+        return str(value)
+    text = str(value).strip()
+    return text if _RECORD_ID_SHAPE.match(text) else None
+
+
+def _safe_cp_event_type(value: Any) -> tuple[str, bool]:
+    """Validate a stored control-plane event type. Returns ``(type, unsafe)``.
+
+    The stored value is externally influenced — whichever producer wrote the
+    ``events`` row chose the string — and ``to_dict`` serializes it verbatim, so
+    it passes a boundary of its own instead of relying on the one ``message``
+    passes. A value survives only when it is an ordinary identifier, is not a
+    bare secret-shaped hex run, and is unchanged by a redaction pass. Anything
+    else fails closed to :data:`UNSAFE_EVENT_TYPE`: the record stays visible as
+    an audit entry, but the value itself is never republished — not verbatim,
+    not partially sanitized, and not rewritten into some other valid-looking
+    type that would misdescribe what happened.
+    """
+    text = ("" if value is None else str(value)).strip()
+    if not text:
+        return ("", False)
+    if _BARE_SECRET_SHAPE.match(text):
+        return (UNSAFE_EVENT_TYPE, True)
+    if not _CP_EVENT_TYPE_SHAPE.match(text):
+        return (UNSAFE_EVENT_TYPE, True)
+    if _redact(text) != text:
+        return (UNSAFE_EVENT_TYPE, True)
+    return (text, False)
+
+
+def _safe_echo(value: Any) -> Any:
+    """Guard a scalar that is echoed back rather than derived from a record.
+
+    Query scope and filter values are caller-supplied and are reflected in the
+    response so an operator can see what was asked. Reflection is still
+    emission: a value redaction would alter, or a bare secret-shaped hex run, is
+    replaced by the placeholder instead of being echoed verbatim. Ordinary
+    scope and filter values pass through untouched.
+    """
+    if value is None or isinstance(value, (int, bool)):
+        return value
+    text = str(value)
+    if _BARE_SECRET_SHAPE.match(text.strip()):
+        return console_redaction.REDACTED
+    return _redact(text)
+
+
+def adapt_cp_events(rows: Iterable[dict[str, Any]]) -> list[WorkflowEvent]:
+    """Adapt control-plane ``events`` rows (joined to work_items) into events.
+
+    Each row is expected to carry ``event_id``, ``event_type``, ``message``,
+    ``created_at`` and the joined work-item ``kind``/``number``. Rows missing
+    an id or type are skipped so a partially written table never raises.
+    """
+    events: list[WorkflowEvent] = []
+    for row in rows or []:
+        try:
+            event_id = _safe_record_id(row.get("event_id"))
+            raw_event_type = (row.get("event_type") or "").strip()
+            if event_id is None or not raw_event_type:
+                continue
+            # The stored type is source data, not a trusted constant: validate
+            # it before it is serialized, exactly as `message` below is redacted
+            # before it is serialized.
+            event_type, event_type_unsafe = _safe_cp_event_type(raw_event_type)
+            kind = row.get("kind")
+            number = row.get("number")
+            issue_no, pr_no = _kind_to_numbers(kind, number)
+            sensitive = event_type_unsafe or any(
+                hint in raw_event_type.lower() for hint in _SENSITIVE_EVENT_HINTS
+            )
+            events.append(
+                WorkflowEvent(
+                    source=SOURCE_CONTROL_PLANE,
+                    event_type=event_type,
+                    event_key=f"cp:{event_id}",
+                    timestamp=_parse_ts(row.get("created_at")),
+                    issue_number=issue_no,
+                    pr_number=pr_no,
+                    # No session_id: the control-plane events table is
+                    # (event_id, work_item_id, event_type, message, created_at)
+                    # and records no session. Inventing one from the work item
+                    # or the message text would be a guess, so this source
+                    # declares the session dimension unsupported instead
+                    # (_SOURCE_FILTER_SUPPORT) and the query layer refuses a
+                    # session filter it cannot honestly answer.
+                    message=_redact(row.get("message")),
+                    correlation_id=_correlation_for(kind, number),
+                    sensitive=sensitive,
+                )
+            )
+        except Exception:
+            # A single malformed row must not sink the whole adaptation.
+            continue
+    return events
+
+
+def adapt_cth_comments(
+    comments: Iterable[dict[str, Any]],
+    *,
+    kind: str,
+    number: int,
+) -> list[WorkflowEvent]:
+    """Adapt Gitea Canonical Thread Handoff (CTH) comments into events.
+
+    Only comments that parse as a CTH (``canonical_thread_handoff.parse_cth_comment``)
+    become events; ordinary comments are ignored. ``kind``/``number`` scope the
+    events to the issue or PR the comments belong to.
+    """
+    # Imported lazily so this module has no import-time dependency on the
+    # handoff parser when only the control-plane adapter is used.
+    from canonical_thread_handoff import is_known_cth_type, parse_cth_comment
+
+    # ``kind``/``number`` are interpolated into event_key and correlation_id, so
+    # they are normalised once here. A scope this adapter cannot express is
+    # refused outright rather than serialized into an identifier.
+    kind = (kind or "").strip().lower()
+    if kind not in ("issue", "pr"):
+        return []
+    try:
+        number = int(number)
+    except (TypeError, ValueError):
+        return []
+
+    issue_no, pr_no = _kind_to_numbers(kind, number)
+    correlation = _correlation_for(kind, number)
+    events: list[WorkflowEvent] = []
+    for comment in comments or []:
+        try:
+            body = comment.get("body") or ""
+            parsed = parse_cth_comment(body)
+            if not parsed:
+                continue
+            fields = parsed.get("fields") or {}
+            cth_type = parsed.get("cth_type") or ""
+            comment_id = _safe_record_id(comment.get("id"))
+            if comment_id is None:
+                continue
+            # The CTH heading is free text: the parser accepts whatever follows
+            # "## CTH:", and only the write and assess paths check it against
+            # the contract. Check it here too — an unrecognised heading is
+            # reported as such rather than serialized into event_type, so
+            # arbitrary, malformed, or secret-shaped heading content has no way
+            # through. Declared types are preserved exactly.
+            cth_type_known = is_known_cth_type(cth_type)
+            # Redaction runs first, and every derived value is taken from the
+            # redacted text — deriving evidence refs from the raw proof would
+            # re-emit exactly what redaction was about to remove.
+            decision = _redact(fields.get("decision"))
+            proof = _redact(fields.get("proof"))
+            next_action = _redact(fields.get("next action"))
+            refs, refs_dropped = _validated_evidence_refs(
+                _extract_evidence_refs(proof, decision)
+            )
+            events.append(
+                WorkflowEvent(
+                    source=SOURCE_GITEA_HANDOFF,
+                    event_type=(
+                        f"handoff:{cth_type.strip()}"
+                        if cth_type_known
+                        else UNKNOWN_HANDOFF_EVENT_TYPE
+                    ),
+                    event_key=f"cth:{kind}:{number}:{comment_id}",
+                    timestamp=_parse_ts(comment.get("created_at")),
+                    actor=_redact((comment.get("user") or {}).get("login")),
+                    role=_redact(fields.get("next owner")),
+                    issue_number=issue_no,
+                    pr_number=pr_no,
+                    # A CTH names its own session when the producer records one;
+                    # it is read from that declared field, never inferred from
+                    # unrelated text.
+                    session_id=_safe_session_id(fields.get("session")),
+                    decision=decision,
+                    message=next_action or _redact(fields.get("status")),
+                    correlation_id=correlation,
+                    evidence_refs=refs,
+                    sensitive=refs_dropped or not cth_type_known,
+                )
+            )
+        except Exception:
+            continue
+    return events
+
+
+# --------------------------------------------------------------------------- #
+# Read-only control-plane event source.                                       #
+# --------------------------------------------------------------------------- #
+
+_CP_EVENTS_QUERY = """
+SELECT e.event_id   AS event_id,
+       e.event_type AS event_type,
+       e.message    AS message,
+       e.created_at AS created_at,
+       w.kind       AS kind,
+       w.number     AS number
+FROM events e
+JOIN work_items w ON e.work_item_id = w.work_item_id
+WHERE w.remote = ? AND w.org = ? AND w.repo = ?
+"""
+
+
+@dataclass(frozen=True)
+class SourceStatus:
+    """Fail-soft status for one timeline source.
+
+    ``supported_filters`` states which filter dimensions this source's records
+    can carry; ``unsupported_filters`` names the requested dimensions it cannot,
+    so an operator can see *why* a source contributed nothing rather than being
+    left to read an empty list as an absence of activity.
+    """
+
+    name: str
+    ok: bool
+    reason: str | None = None
+    count: int = 0
+    supported_filters: tuple[str, ...] = ()
+    unsupported_filters: tuple[str, ...] = ()
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "name": self.name,
+            "ok": self.ok,
+            "reason": self.reason,
+            "count": self.count,
+            "supported_filters": list(self.supported_filters),
+            "unsupported_filters": list(self.unsupported_filters),
+        }
+
+
+def _cp_status(*, ok: bool, reason: str | None = None, count: int = 0) -> SourceStatus:
+    return SourceStatus(
+        SOURCE_CONTROL_PLANE,
+        ok=ok,
+        # A failure reason is serialized like any other field and is often an
+        # exception string carrying a path or a transport error, so it crosses
+        # the redaction boundary too. Static reasons pass through unchanged.
+        reason=_redact(reason),
+        count=count,
+        supported_filters=_SOURCE_FILTER_SUPPORT[SOURCE_CONTROL_PLANE],
+    )
+
+
+def _handoff_status(*, ok: bool, reason: str | None = None, count: int = 0) -> SourceStatus:
+    return SourceStatus(
+        SOURCE_GITEA_HANDOFF,
+        ok=ok,
+        # Same boundary as the control-plane status: this reason can quote an
+        # error raised by a live authenticated fetch.
+        reason=_redact(reason),
+        count=count,
+        supported_filters=_SOURCE_FILTER_SUPPORT[SOURCE_GITEA_HANDOFF],
+    )
+
+
+def read_cp_events(
+    *,
+    remote: str,
+    org: str,
+    repo: str,
+    db_path: str | None = None,
+) -> tuple[list[WorkflowEvent], SourceStatus]:
+    """Read scoped control-plane events read-only. Never creates the DB.
+
+    Opens the SQLite file through a ``mode=ro`` URI: a health/timeline read
+    must never create directories or run the schema migration that
+    ``ControlPlaneDB()`` performs on construction. A missing or unreadable DB
+    degrades to a status with a reason.
+    """
+    path = (db_path or control_plane_db.default_db_path()).strip()
+    conn: sqlite3.Connection | None = None
+    try:
+        conn = sqlite3.connect(f"file:{path}?mode=ro", uri=True)
+        conn.row_factory = sqlite3.Row
+        cursor = conn.execute(_CP_EVENTS_QUERY, (remote, org, repo))
+        rows = [dict(r) for r in cursor.fetchall()]
+    except sqlite3.OperationalError as exc:
+        return ([], _cp_status(ok=False, reason=f"control-plane DB unavailable: {exc}"))
+    except sqlite3.Error as exc:
+        return ([], _cp_status(ok=False, reason=f"control-plane read failed: {exc}"))
+    finally:
+        if conn is not None:
+            conn.close()
+    events = adapt_cp_events(rows)
+    return (events, _cp_status(ok=True, count=len(events)))
+
+
+# --------------------------------------------------------------------------- #
+# Filter, sort, paginate.                                                     #
+# --------------------------------------------------------------------------- #
+
+
+def filter_events(
+    events: Iterable[WorkflowEvent],
+    *,
+    issue: int | None = None,
+    pr: int | None = None,
+    session: str | None = None,
+) -> list[WorkflowEvent]:
+    """Filter events by issue number, PR number, and/or session id.
+
+    Filters are conjunctive. A filter that names a dimension an event does not
+    carry excludes that event (an issue filter excludes PR-only events).
+    """
+    out: list[WorkflowEvent] = []
+    for ev in events:
+        if issue is not None and ev.issue_number != issue:
+            continue
+        if pr is not None and ev.pr_number != pr:
+            continue
+        if session is not None and ev.session_id != session:
+            continue
+        out.append(ev)
+    return out
+
+
+def sort_events(events: Iterable[WorkflowEvent]) -> list[WorkflowEvent]:
+    """Return events in stable timeline order (ascending)."""
+    return sorted(events, key=lambda ev: ev.sort_key())
+
+
+@dataclass(frozen=True)
+class TimelinePage:
+    """One page of the sorted, filtered timeline."""
+
+    events: tuple[WorkflowEvent, ...]
+    total: int
+    limit: int
+    offset: int
+
+    @property
+    def next_offset(self) -> int | None:
+        nxt = self.offset + len(self.events)
+        return nxt if nxt < self.total else None
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "events": [ev.to_dict() for ev in self.events],
+            "pagination": {
+                "total": self.total,
+                "limit": self.limit,
+                "offset": self.offset,
+                "returned": len(self.events),
+                "next_offset": self.next_offset,
+                "has_more": self.next_offset is not None,
+            },
+        }
+
+
+_MAX_LIMIT = 500
+_DEFAULT_LIMIT = 50
+
+
+def _coerce_bounds(limit: int | None, offset: int | None) -> tuple[int, int]:
+    try:
+        lim = int(limit) if limit is not None else _DEFAULT_LIMIT
+    except (TypeError, ValueError):
+        lim = _DEFAULT_LIMIT
+    try:
+        off = int(offset) if offset is not None else 0
+    except (TypeError, ValueError):
+        off = 0
+    lim = max(1, min(lim, _MAX_LIMIT))
+    off = max(0, off)
+    return (lim, off)
+
+
+def paginate(events: list[WorkflowEvent], *, limit: int | None, offset: int | None) -> TimelinePage:
+    lim, off = _coerce_bounds(limit, offset)
+    window = events[off : off + lim]
+    return TimelinePage(events=tuple(window), total=len(events), limit=lim, offset=off)
+
+
+# --------------------------------------------------------------------------- #
+# Composition — load_timeline aggregates all sources, fail-soft.              #
+# --------------------------------------------------------------------------- #
+
+# A comment source is a callable that, given (kind, number), returns the raw
+# Gitea comment list for that issue/PR. The route supplies a live fail-soft
+# fetcher; tests supply a fixture. When None, the handoff source is reported as
+# not-run (never silently empty-and-healthy).
+CommentSource = Callable[[str, int], list[dict[str, Any]]]
+
+
+@dataclass(frozen=True)
+class TimelineSnapshot:
+    """One answered timeline query.
+
+    ``ok`` is False when the query could not be answered as asked — currently
+    when a requested filter dimension no surviving source can carry was
+    supplied. The page is then empty *and* the snapshot says so, because an
+    ``ok`` empty page is a claim that no such activity exists.
+    """
+
+    schema_version: int
+    remote: str
+    org: str
+    repo: str
+    filters: dict[str, Any]
+    page: TimelinePage
+    sources: tuple[SourceStatus, ...]
+    ok: bool = True
+    error: dict[str, Any] | None = None
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "ok": self.ok,
+            "error": self.error,
+            "schema_version": self.schema_version,
+            # Scope and filters are echoed caller input, not derived record
+            # data. Reflecting a value is still emitting it, so both cross the
+            # same boundary; ordinary scope and filter values are unchanged.
+            "scope": {
+                "remote": _safe_echo(self.remote),
+                "org": _safe_echo(self.org),
+                "repo": _safe_echo(self.repo),
+            },
+            "filters": {key: _safe_echo(value) for key, value in self.filters.items()},
+            "sources": [s.to_dict() for s in self.sources],
+            **self.page.to_dict(),
+        }
+
+
+def _unanswerable_reasons(
+    statuses: Iterable[SourceStatus], unanswerable: Iterable[str]
+) -> list[dict[str, str]]:
+    """Explain, per source, why each unanswerable dimension went unanswered."""
+    out: list[dict[str, str]] = []
+    for status in statuses:
+        for dim in unanswerable:
+            if dim not in status.supported_filters:
+                reason = _SOURCE_FILTER_LIMITS.get(
+                    (status.name, dim), f"this source's records carry no {dim} identity"
+                )
+            elif not status.ok:
+                reason = (
+                    f"this source can carry {dim} but did not run: "
+                    f"{status.reason or 'unavailable'}"
+                )
+            else:
+                continue
+            out.append({"source": status.name, "filter": dim, "reason": reason})
+    return out
+
+
+def load_timeline(
+    *,
+    remote: str,
+    org: str,
+    repo: str,
+    issue: int | None = None,
+    pr: int | None = None,
+    session: str | None = None,
+    limit: int | None = None,
+    offset: int | None = None,
+    db_path: str | None = None,
+    comment_source: CommentSource | None = None,
+) -> TimelineSnapshot:
+    """Aggregate every timeline source into one filtered, paginated snapshot.
+
+    Sources are read independently and fail soft: an unavailable source
+    contributes a ``SourceStatus`` with ``ok=False`` and a reason, and never
+    collapses the whole timeline. The handoff source only runs when a specific
+    issue or PR is requested (a handoff comment belongs to one thread) and a
+    ``comment_source`` is available; otherwise it is reported as ``not run``
+    rather than as an empty-and-healthy source.
+
+    A filter dimension that no surviving source can carry — a ``session``
+    filter when the only source that ran is the control plane, whose events
+    record no session — is refused with ``ok=False`` and a structured error
+    instead of being answered with an empty page.
+    """
+    all_events: list[WorkflowEvent] = []
+    statuses: list[SourceStatus] = []
+
+    cp_events, cp_status = read_cp_events(remote=remote, org=org, repo=repo, db_path=db_path)
+    all_events.extend(cp_events)
+    statuses.append(cp_status)
+
+    # Gitea handoff comments are thread-scoped: only fetch when the caller
+    # narrowed to one issue or PR, and only when a source was provided.
+    handoff_target: tuple[str, int] | None = None
+    if pr is not None:
+        handoff_target = ("pr", pr)
+    elif issue is not None:
+        handoff_target = ("issue", issue)
+
+    if handoff_target is None:
+        statuses.append(
+            _handoff_status(
+                ok=False,
+                reason="not run: handoff comments are thread-scoped; filter by issue or pr to include them",
+            )
+        )
+    elif comment_source is None:
+        statuses.append(
+            _handoff_status(
+                ok=False,
+                reason="not run: no comment source configured for this timeline read",
+            )
+        )
+    else:
+        kind, number = handoff_target
+        try:
+            comments = comment_source(kind, number) or []
+            handoff_events = adapt_cth_comments(comments, kind=kind, number=number)
+            all_events.extend(handoff_events)
+            statuses.append(_handoff_status(ok=True, count=len(handoff_events)))
+        except Exception as exc:  # fail soft: a fetch/parse error degrades this source only
+            statuses.append(_handoff_status(ok=False, reason=f"handoff source failed: {exc}"))
+
+    requested = tuple(
+        name
+        for name, value in ((FILTER_ISSUE, issue), (FILTER_PR, pr), (FILTER_SESSION, session))
+        if value is not None
+    )
+    statuses = [
+        replace(
+            status,
+            unsupported_filters=tuple(
+                dim for dim in requested if dim not in status.supported_filters
+            ),
+        )
+        for status in statuses
+    ]
+    filters = {"issue": issue, "pr": pr, "session": session}
+
+    # A dimension is answerable only if a source that actually ran can carry it.
+    # If none can, refuse: an empty page would assert "no such activity", which
+    # is a claim this timeline is not in a position to make.
+    answerable: set[str] = set()
+    for status in statuses:
+        if status.ok:
+            answerable.update(status.supported_filters)
+    unanswerable = tuple(dim for dim in requested if dim not in answerable)
+
+    if unanswerable:
+        return TimelineSnapshot(
+            schema_version=TIMELINE_SCHEMA_VERSION,
+            remote=remote,
+            org=org,
+            repo=repo,
+            filters=filters,
+            page=paginate([], limit=limit, offset=offset),
+            sources=tuple(statuses),
+            ok=False,
+            error={
+                "code": "filter_not_supported",
+                "unsupported_filters": list(unanswerable),
+                "detail": (
+                    "no timeline source that ran can answer "
+                    + ", ".join(f"'{dim}'" for dim in unanswerable)
+                    + "; the result is refused rather than returned empty"
+                ),
+                "sources": _unanswerable_reasons(statuses, unanswerable),
+            },
+        )
+
+    filtered = filter_events(all_events, issue=issue, pr=pr, session=session)
+    ordered = sort_events(filtered)
+    page = paginate(ordered, limit=limit, offset=offset)
+
+    return TimelineSnapshot(
+        schema_version=TIMELINE_SCHEMA_VERSION,
+        remote=remote,
+        org=org,
+        repo=repo,
+        filters=filters,
+        page=page,
+        sources=tuple(statuses),
+    )
+
+
+def snapshot_to_dict(snapshot: TimelineSnapshot) -> dict[str, Any]:
+    return snapshot.to_dict()