Merge branch 'master' into feat/issue-641-runtime-session-view

Compose runtime health with inventory sessions/namespaces/worktrees into a
live /sessions page and JSON API. Surface stale PID/lease flags and durable
contamination markers when detectable. Recovery links name sanctioned
reconnect/restart paths only — no kill controls.

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

docs/mcp-restart-classes.md

@@ -1,53 +0,0 @@
-# MCP restart classes and blast-radius permissions (#663)
-
-This is the machine-enforced class matrix used by
-`restart_coordinator.RESTART_CLASS_POLICIES`. It implements the narrower-first
-recovery ladder from #655 and the authorization policy from #656, using the
-path inventory from #657 and the impact coordinator from #658. Product and
-delivery lineage: vision #652 and roadmap #653.
-
-Unknown class names are denied. The coordinator requires both the class
-permission and an eligible request role. Approval gates are additional: a
-caller cannot turn a request permission into execution authority.
-
-| Restart class | Required permission | Expected blast radius | Drain requirement | Approval requirement | Audit requirement | Recovery behavior |
-|---|---|---|---|---|---|---|
-| `client_reconnect` | `mcp.reconnect.client` | none | none | self service | class, actor, client namespace, reason, outcome | Reconnect only the caller's client transport. No daemon or peer work changes. |
-| `session_reconnect` | `mcp.reconnect.session` | low | requesting-session safe point | self service | class, actor, session, reason, outcome | Rebind identity, capability, and workspace state for one session. |
-| `worker_restart` | `mcp.restart.worker.request` | low | target worker | controller approval + automated gates | class, actor, worker, approval, scoped drain, outcome | Restart one worker after its own leases and mutations drain. |
-| `role_runtime_restart` | `mcp.restart.role_runtime.request` | medium | target role runtime | controller approval + automated gates | class, actor, role namespace, approval, scoped drain, outcome | Restart and re-probe one role runtime; unrelated roles remain available. |
-| `connector_restart` | `mcp.restart.connector.request` | medium | target connector | controller approval + automated gates | class, actor, connector, approval, scoped drain, outcome | Restart one connector while unrelated runtimes remain available. |
-| `configuration_reload` | `mcp.reload.configuration.request` | low | mutation quiesce | controller approval + automated gates | class, actor, configuration revision, approval, outcome | Gracefully reload configuration without replacing the daemon. |
-| `rolling_mcp_restart` | `mcp.restart.rolling.request` | medium | one instance at a time | controller approval + automated gates | class, actor, instance order, approval, per-instance drains, outcome | Drain, restart, verify, and restore each instance before advancing. |
-| `full_mcp_restart` | `mcp.restart.full.request` | high | all sessions and mutations | controller approval + automated gates | class, actor, full impact, approval, full drain proof, outcome | Replace the complete MCP runtime only after a verified full drain. |
-| `host_restart` | `mcp.restart.host.request` | high | all host work | controller approval + infrastructure operator | class, actor, host/change or incident id, approval, full drain proof, outcome | Hand off to infrastructure ownership and reconcile every runtime afterward. |
-
-## Drain boundary
-
-Only `full_mcp_restart` and `host_restart` set `full_drain_required=true`.
-Reconnects and configuration reloads do not disrupt peer sessions. Worker,
-role-runtime, and connector restarts evaluate only their explicitly named
-target. Rolling restart drains one instance at a time. Missing required target
-scope denies the request rather than silently widening it to a full restart.
-
-## Permission and approval boundary
-
-Author, reviewer, merger, and reconciler roles may self-request reconnects and
-request scoped worker/role/connector/reload recovery. They cannot request
-rolling, full, or host restart classes. Controller/operator/admin roles may
-request the broader classes, while execution remains operator/admin-owned.
-Controller approval is independently required for every class above a session
-reconnect. Host restart additionally requires infrastructure-operator proof.
-
-The MCP request tool derives class permissions from its authenticated runtime
-role. It does not accept caller-supplied permissions. Controller and operator
-authorization are read from the already-running daemon environment, never
-from a request argument.
-
-## Audit and failure behavior
-
-Every impact audit and every console restart/reload audit includes a
-`restart_class` field. The impact audit also includes the exact
-`required_permission`. Unknown classes, missing permissions, ineligible roles,
-missing approval, missing scoped targets, and incomplete inventory all deny
-fail closed. Manual process kills remain forbidden and contaminating (#630).

docs/mcp-restart-coordinator.md

@@ -12,12 +12,6 @@ restart/reload/kill paths). The **mutative apply** path — actually performing
 restart — is a later child gated by a drain proof and is explicitly out of
 scope here.
 
-The coordinator now routes every request through the restart-class policy
-matrix defined for #663. See
-[`mcp-restart-classes.md`](./mcp-restart-classes.md) for permissions, expected
-blast radius, scoped drain and approval requirements, audit fields, and
-recovery behavior for all nine classes.
-
 ## Components
 
 | Piece | Where | Responsibility |
@@ -83,10 +77,7 @@ authorization is present.
 ```text
 gitea_request_mcp_restart(remote, host, org, repo,
                           dry_run=True, request_override=False,
-                          session_id=None, limit=200,
+                          session_id=None, limit=200)
-                          restart_class="full_mcp_restart",
-                          target_session_id=None, target_role=None,
-                          target_connector=None)
 ```
 
 Read-only, dry-run, and it **never restarts anything**. `apply_supported` is
@@ -96,8 +87,7 @@ apply is gated by a drain proof (a separate child).
 ## Audit
 
 Every evaluation carries an `audit_record` (event, coordinator version, verdict,
-restart class, required permission, allow decision, blast radius, counts,
+allow decision, blast radius, counts, timestamp) so restart decisions are
-timestamp) so restart decisions are
 auditable. No secrets flow through the coordinator — session ids, pids, and
 profiles are operational metadata only.
 

docs/webui-local-dev.md

@@ -77,7 +77,9 @@ 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) |
+| `/sessions` | Runtime and session view (#641) — health + inventory sessions/namespaces/worktrees |
+| `/api/sessions` | JSON export for the runtime/session view |
+| `/api/v1/sessions` | Versioned alias of `/api/sessions` |
 | `/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 |
@@ -284,11 +286,26 @@ The header carries two read-only status badges — an **environment** badge
 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`,
+Not-yet-implemented surfaces (`/inventory`, `/timeline`, `/policy`,
-`/policy`, `/insights`) resolve to graceful read-only stub pages instead of
+`/insights`) resolve to graceful read-only stub pages instead of 404s; their
-404s; their backing views land in later child issues of #631 (the inventory
+backing views land in later child issues of #631 (the inventory surfaces are
-surfaces are backed by #636). Mutating methods on stub routes still fail closed
+backed by #636). Mutating methods on stub routes still fail closed with
-with `read-only-mvp`.
+`read-only-mvp`.
+
+### Runtime and sessions (#641)
+
+`/sessions` is a live Phase 1 read-only view that composes:
+
+* runtime health from `#430` (profile, role, identity, master parity, stale warning)
+* control-plane sessions / leases and filesystem locks / worktrees / namespaces from `#636`
+* durable contamination markers when detectable (`#630` runtime recovery, `#671` stable-branch push)
+
+It surfaces stale indicators (dead PID, expired lease) and never silences an
+active contamination marker. Recovery links point only at sanctioned
+reconnect/operator restart docs (`docs/mcp-namespace-eof-recovery.md`,
+`docs/mcp-namespace-health.md`, `docs/mcp-restart-path-inventory.md`, this
+document). The page does **not** restart, kill, or take over sessions; manual
+`pkill` of MCP daemons is contamination, not recovery.
 
 ## System-health dashboard (#639)
 

gitea_mcp_server.py

@@ -22342,15 +22342,10 @@ def gitea_request_mcp_restart(
     request_override: bool = False,
     session_id: str | None = None,
     limit: int = 200,
-    restart_class: str = "full_mcp_restart",
-    target_session_id: str | None = None,
-    target_role: str | None = None,
-    target_connector: str | None = None,
 ) -> dict:
     """Evaluate a proposed MCP restart and return an impact preview (#658).
 
-    Central restart coordinator: resolves the requested restart class, gathers
+    Central restart coordinator: gathers live control-plane state (sessions,
-    live control-plane state (sessions,
     leases/locks, in-flight issue/PR work, mutations, worktrees) and returns a
     blast-radius impact report with a ``safe`` / ``unsafe`` / ``override``
     verdict, so the console (#642/#652) and operators can see what a restart
@@ -22444,9 +22439,6 @@ def gitea_request_mcp_restart(
 
     profile = get_profile()
     profile_name = (profile.get("profile_name") or "").strip() or "session"
-    requester_role = (
-        profile.get("role_kind") or profile.get("role") or ""
-    ).strip().lower()
     sid = (session_id or "").strip() or f"{profile_name}-{os.getpid()}"
 
     # Override authority is read from the environment only — a worker session
@@ -22456,15 +22448,6 @@ def gitea_request_mcp_restart(
         (os.environ.get("GITEA_OPERATOR_RESTART_OVERRIDE_AUTHORIZATION") or "").strip()
     )
     operator_override = bool(request_override and operator_authorized)
-    controller_approved = bool(
-        (
-            os.environ.get("GITEA_CONTROLLER_RESTART_APPROVAL_AUTHORIZATION")
-            or ""
-        ).strip()
-    )
-    requester_permissions = restart_coordinator.permissions_for_role(
-        requester_role
-    )
 
     inventory = {
         "sessions": sessions,
@@ -22479,14 +22462,6 @@ def gitea_request_mcp_restart(
         operator_override=operator_override,
         requesting_session_id=sid,
         dry_run=True,  # coordinator is always analysis-only (#658)
-        restart_class=restart_class,
-        requester_role=requester_role,
-        requester_permissions=requester_permissions,
-        controller_approved=controller_approved,
-        operator_authorized=operator_authorized,
-        target_session_id=target_session_id,
-        target_role=target_role,
-        target_connector=target_connector,
     )
 
     payload = report.as_dict()
@@ -22498,9 +22473,6 @@ def gitea_request_mcp_restart(
     payload["requesting_session_id"] = sid
     payload["operator_override_requested"] = bool(request_override)
     payload["operator_override_authorized"] = operator_authorized
-    payload["controller_approval_authorized"] = controller_approved
-    payload["requester_role"] = requester_role
-    payload["requester_permissions"] = list(requester_permissions)
     payload["apply_supported"] = False
     if not dry_run:
         payload["reasons"] = list(payload.get("reasons") or []) + [

restart_coordinator.py

@@ -28,12 +28,11 @@ from __future__ import annotations
 
 from dataclasses import dataclass, field
 from datetime import datetime, timezone
-from enum import Enum
 from typing import Any, Mapping, Sequence
 
 import lease_lifecycle
 
-COORDINATOR_VERSION = "1.1.0-issue-663"
+COORDINATOR_VERSION = "1.0.0-issue-658"
 
 # Restart verdicts. Exactly the three the acceptance criteria name.
 VERDICT_SAFE = "safe"
@@ -55,194 +54,6 @@ LEASE_FRESHNESS_LIVE = "active"
 DEFAULT_SESSION_HEARTBEAT_STALE_SECONDS = 900
 
 
-class RestartClass(str, Enum):
-    """The only restart/recovery classes accepted by the coordinator."""
-
-    CLIENT_RECONNECT = "client_reconnect"
-    SESSION_RECONNECT = "session_reconnect"
-    WORKER_RESTART = "worker_restart"
-    ROLE_RUNTIME_RESTART = "role_runtime_restart"
-    CONNECTOR_RESTART = "connector_restart"
-    CONFIGURATION_RELOAD = "configuration_reload"
-    ROLLING_MCP_RESTART = "rolling_mcp_restart"
-    FULL_MCP_RESTART = "full_mcp_restart"
-    HOST_RESTART = "host_restart"
-
-
-@dataclass(frozen=True)
-class RestartClassPolicy:
-    """Least-privilege policy for one :class:`RestartClass`."""
-
-    restart_class: RestartClass
-    required_permission: str
-    expected_blast_radius: str
-    drain_requirement: str
-    full_drain_required: bool
-    approval_requirement: str
-    audit_requirement: str
-    recovery_behavior: str
-    request_roles: tuple[str, ...]
-    execution_roles: tuple[str, ...]
-
-    def as_dict(self) -> dict[str, Any]:
-        return {
-            "restart_class": self.restart_class.value,
-            "required_permission": self.required_permission,
-            "expected_blast_radius": self.expected_blast_radius,
-            "drain_requirement": self.drain_requirement,
-            "full_drain_required": self.full_drain_required,
-            "approval_requirement": self.approval_requirement,
-            "audit_requirement": self.audit_requirement,
-            "recovery_behavior": self.recovery_behavior,
-            "request_roles": list(self.request_roles),
-            "execution_roles": list(self.execution_roles),
-        }
-
-
-WORKER_ROLES = ("author", "reviewer", "merger", "reconciler")
-CONTROL_ROLES = ("controller", "operator", "admin")
-ALL_REQUEST_ROLES = WORKER_ROLES + CONTROL_ROLES
-
-RESTART_CLASS_POLICIES: dict[RestartClass, RestartClassPolicy] = {
-    RestartClass.CLIENT_RECONNECT: RestartClassPolicy(
-        RestartClass.CLIENT_RECONNECT,
-        "mcp.reconnect.client",
-        BLAST_NONE,
-        "none",
-        False,
-        "self_service",
-        "record class, actor, client namespace, reason, and outcome",
-        "Reconnect only the caller's client transport; no daemon or peer session changes.",
-        ALL_REQUEST_ROLES,
-        ALL_REQUEST_ROLES,
-    ),
-    RestartClass.SESSION_RECONNECT: RestartClassPolicy(
-        RestartClass.SESSION_RECONNECT,
-        "mcp.reconnect.session",
-        BLAST_LOW,
-        "requesting_session_safe_point",
-        False,
-        "self_service",
-        "record class, actor, session id, reason, and outcome",
-        "Rebind identity, capability, and workspace state for one session.",
-        ALL_REQUEST_ROLES,
-        ALL_REQUEST_ROLES,
-    ),
-    RestartClass.WORKER_RESTART: RestartClassPolicy(
-        RestartClass.WORKER_RESTART,
-        "mcp.restart.worker.request",
-        BLAST_LOW,
-        "target_worker",
-        False,
-        "controller_approval_and_automated_gates",
-        "record class, actor, target worker, approval, drain proof, and outcome",
-        "Restart one worker after its own lease and mutation scope is drained.",
-        ALL_REQUEST_ROLES,
-        ("operator", "admin"),
-    ),
-    RestartClass.ROLE_RUNTIME_RESTART: RestartClassPolicy(
-        RestartClass.ROLE_RUNTIME_RESTART,
-        "mcp.restart.role_runtime.request",
-        BLAST_MEDIUM,
-        "target_role_runtime",
-        False,
-        "controller_approval_and_automated_gates",
-        "record class, actor, role namespace, approval, drain proof, and outcome",
-        "Restart only the selected role runtime and then re-probe that namespace.",
-        ALL_REQUEST_ROLES,
-        ("operator", "admin"),
-    ),
-    RestartClass.CONNECTOR_RESTART: RestartClassPolicy(
-        RestartClass.CONNECTOR_RESTART,
-        "mcp.restart.connector.request",
-        BLAST_MEDIUM,
-        "target_connector",
-        False,
-        "controller_approval_and_automated_gates",
-        "record class, actor, connector id, approval, drain proof, and outcome",
-        "Restart one connector while unrelated role runtimes remain available.",
-        ALL_REQUEST_ROLES,
-        ("operator", "admin"),
-    ),
-    RestartClass.CONFIGURATION_RELOAD: RestartClassPolicy(
-        RestartClass.CONFIGURATION_RELOAD,
-        "mcp.reload.configuration.request",
-        BLAST_LOW,
-        "mutation_quiesce",
-        False,
-        "controller_approval_and_automated_gates",
-        "record class, actor, configuration revision, approval, and outcome",
-        "Gracefully reload configuration without replacing the daemon process.",
-        ALL_REQUEST_ROLES,
-        ("operator", "admin"),
-    ),
-    RestartClass.ROLLING_MCP_RESTART: RestartClassPolicy(
-        RestartClass.ROLLING_MCP_RESTART,
-        "mcp.restart.rolling.request",
-        BLAST_MEDIUM,
-        "one_instance_at_a_time",
-        False,
-        "controller_approval_and_automated_gates",
-        "record class, actor, instance order, approval, per-instance drains, and outcome",
-        "Drain, restart, verify, and restore one instance before advancing to the next.",
-        CONTROL_ROLES,
-        ("operator", "admin"),
-    ),
-    RestartClass.FULL_MCP_RESTART: RestartClassPolicy(
-        RestartClass.FULL_MCP_RESTART,
-        "mcp.restart.full.request",
-        BLAST_HIGH,
-        "all_sessions_and_mutations",
-        True,
-        "controller_approval_and_automated_gates",
-        "record class, actor, full impact report, approval, drain proof, and outcome",
-        "Stop and restore the complete MCP runtime only after a verified full drain.",
-        CONTROL_ROLES,
-        ("operator", "admin"),
-    ),
-    RestartClass.HOST_RESTART: RestartClassPolicy(
-        RestartClass.HOST_RESTART,
-        "mcp.restart.host.request",
-        BLAST_HIGH,
-        "all_host_work",
-        True,
-        "controller_approval_plus_infrastructure_operator",
-        "record class, actor, host, incident or change id, approval, drain proof, and outcome",
-        "Hand off to infrastructure ownership; reconcile every runtime after the host returns.",
-        ("controller", "operator", "admin"),
-        ("operator", "admin"),
-    ),
-}
-
-
-def resolve_restart_class(value: RestartClass | str) -> RestartClass:
-    """Resolve a restart class or fail closed for an unknown value."""
-
-    if isinstance(value, RestartClass):
-        return value
-    try:
-        return RestartClass(str(value).strip())
-    except ValueError as exc:
-        raise ValueError(f"unknown restart class {value!r}; deny (fail closed)") from exc
-
-
-def restart_class_policy(value: RestartClass | str) -> RestartClassPolicy:
-    """Return the canonical policy for *value*."""
-
-    return RESTART_CLASS_POLICIES[resolve_restart_class(value)]
-
-
-def permissions_for_role(role: str | None) -> tuple[str, ...]:
-    """Return request permissions granted to a workflow role by this policy."""
-
-    normalized = str(role or "").strip().lower()
-    return tuple(
-        policy.required_permission
-        for policy in RESTART_CLASS_POLICIES.values()
-        if normalized in policy.request_roles
-    )
-
-
 def _utc_now() -> datetime:
     return datetime.now(timezone.utc)
 
@@ -264,7 +75,6 @@ class SessionImpact:
     heartbeat_stale: bool
     is_requester: bool
     live: bool
-    connector: str | None = None
 
     def as_dict(self) -> dict[str, Any]:
         return {
@@ -277,7 +87,6 @@ class SessionImpact:
             "heartbeat_stale": self.heartbeat_stale,
             "is_requester": self.is_requester,
             "live": self.live,
-            "connector": self.connector,
         }
 
 
@@ -296,7 +105,6 @@ class LeaseImpact:
     disruptive: bool
     is_mutation: bool
     is_critical_section: bool
-    connector: str | None = None
 
     def as_dict(self) -> dict[str, Any]:
         return {
@@ -311,7 +119,6 @@ class LeaseImpact:
             "disruptive": self.disruptive,
             "is_mutation": self.is_mutation,
             "is_critical_section": self.is_critical_section,
-            "connector": self.connector,
         }
 
 
@@ -320,13 +127,6 @@ class RestartImpactReport:
     """Impact preview DTO returned to the console / operator (#642/#652)."""
 
     coordinator_version: str
-    restart_class: str
-    restart_policy: dict[str, Any]
-    policy_enforced: bool
-    permission_authorized: bool
-    role_authorized: bool
-    approval_satisfied: bool
-    authorization_reasons: list[str]
     evaluated_at: str
     dry_run: bool
     restart_performed: bool
@@ -353,13 +153,6 @@ class RestartImpactReport:
     def as_dict(self) -> dict[str, Any]:
         return {
             "coordinator_version": self.coordinator_version,
-            "restart_class": self.restart_class,
-            "restart_policy": dict(self.restart_policy),
-            "policy_enforced": self.policy_enforced,
-            "permission_authorized": self.permission_authorized,
-            "role_authorized": self.role_authorized,
-            "approval_satisfied": self.approval_satisfied,
-            "authorization_reasons": list(self.authorization_reasons),
             "evaluated_at": self.evaluated_at,
             "dry_run": self.dry_run,
             "restart_performed": self.restart_performed,
@@ -413,7 +206,6 @@ def _classify_session(
             requesting_session_id and session_id == requesting_session_id
         ),
         live=live,
-        connector=(str(row.get("connector") or "").strip() or None),
     )
 
 
@@ -466,7 +258,6 @@ def _classify_lease(row: Mapping[str, Any]) -> LeaseImpact:
         disruptive=disruptive,
         is_mutation=is_mutation,
         is_critical_section=disruptive,
-        connector=(str(row.get("connector") or "").strip() or None),
     )
 
 
@@ -488,14 +279,6 @@ def evaluate_restart_impact(
     requesting_session_id: str | None = None,
     dry_run: bool = True,
     session_heartbeat_stale_seconds: int = DEFAULT_SESSION_HEARTBEAT_STALE_SECONDS,
-    restart_class: RestartClass | str | None = None,
-    requester_role: str | None = None,
-    requester_permissions: Sequence[str] | None = None,
-    controller_approved: bool = False,
-    operator_authorized: bool = False,
-    target_session_id: str | None = None,
-    target_role: str | None = None,
-    target_connector: str | None = None,
 ) -> RestartImpactReport:
     """Evaluate a proposed MCP restart and return an impact preview.
 
@@ -518,61 +301,6 @@ def evaluate_restart_impact(
     """
     moment = now or _utc_now()
     reasons: list[str] = []
-    authorization_reasons: list[str] = []
-
-    # ``None`` preserves the pre-#663 impact-only API for callers that have not
-    # yet been migrated. All MCP requests pass an explicit class and therefore
-    # take the fail-closed policy path.
-    policy_enforced = restart_class is not None
-    try:
-        resolved_class = resolve_restart_class(
-            restart_class or RestartClass.FULL_MCP_RESTART
-        )
-        policy = RESTART_CLASS_POLICIES[resolved_class]
-        unknown_class = False
-    except ValueError as exc:
-        resolved_class = None
-        policy = None
-        unknown_class = True
-        authorization_reasons.append(str(exc))
-
-    normalized_role = str(requester_role or "").strip().lower()
-    granted = {str(p).strip() for p in (requester_permissions or ())}
-    if policy_enforced and policy is not None:
-        permission_authorized = policy.required_permission in granted
-        role_authorized = normalized_role in policy.request_roles
-        if not permission_authorized:
-            authorization_reasons.append(
-                f"missing required permission {policy.required_permission!r}"
-            )
-        if not role_authorized:
-            authorization_reasons.append(
-                f"role {normalized_role or 'unknown'!r} may not request "
-                f"{policy.restart_class.value}"
-            )
-    elif unknown_class:
-        permission_authorized = False
-        role_authorized = False
-    else:
-        permission_authorized = True
-        role_authorized = True
-
-    if policy_enforced and policy is not None:
-        approval = policy.approval_requirement
-        if approval == "self_service":
-            approval_satisfied = True
-        elif approval == "controller_approval_plus_infrastructure_operator":
-            approval_satisfied = bool(controller_approved and operator_authorized)
-        else:
-            approval_satisfied = bool(controller_approved)
-        if not approval_satisfied:
-            authorization_reasons.append(
-                f"approval requirement not satisfied: {approval}"
-            )
-    elif unknown_class:
-        approval_satisfied = False
-    else:
-        approval_satisfied = True
 
     inventory_complete = bool(inventory.get("inventory_complete", False))
     incomplete_reasons = [str(r) for r in (inventory.get("incomplete_reasons") or [])]
@@ -595,67 +323,15 @@ def evaluate_restart_impact(
     ]
     lease_impacts = [_classify_lease(l) for l in leases_raw]
 
-    # Route impact through the selected class. Narrow classes never inherit a
+    # Only *other* live sessions and live leases constitute blast radius: a
-    # full-runtime drain merely because unrelated work exists.
+    # restart that would kill only the requesting session with no other work in
-    target_complete = True
+    # flight is safe.
-    if resolved_class in {
-        RestartClass.CLIENT_RECONNECT,
-        RestartClass.SESSION_RECONNECT,
-        RestartClass.CONFIGURATION_RELOAD,
-    }:
-        scoped_sessions: list[SessionImpact] = []
-        scoped_leases: list[LeaseImpact] = []
-    elif resolved_class == RestartClass.WORKER_RESTART:
-        selected_session = (target_session_id or "").strip()
-        target_complete = bool(selected_session)
-        scoped_sessions = [
-            s for s in session_impacts if s.session_id == selected_session
-        ]
-        scoped_leases = [
-            l for l in lease_impacts if l.session_id == selected_session
-        ]
-    elif resolved_class == RestartClass.ROLE_RUNTIME_RESTART:
-        selected_role = (target_role or "").strip().lower()
-        target_complete = bool(selected_role)
-        scoped_sessions = [
-            s for s in session_impacts if str(s.role or "").lower() == selected_role
-        ]
-        scoped_leases = [
-            l for l in lease_impacts if str(l.role or "").lower() == selected_role
-        ]
-    elif resolved_class == RestartClass.CONNECTOR_RESTART:
-        selected_connector = (target_connector or "").strip()
-        target_complete = bool(selected_connector)
-        scoped_sessions = [
-            s for s in session_impacts if s.connector == selected_connector
-        ]
-        scoped_leases = [
-            l for l in lease_impacts if l.connector == selected_connector
-        ]
-    else:
-        scoped_sessions = list(session_impacts)
-        scoped_leases = list(lease_impacts)
-
-    if policy_enforced and not target_complete:
-        authorization_reasons.append(
-            f"target required for {resolved_class.value if resolved_class else 'unknown class'}"
-        )
-
     other_live_sessions = [
-        s for s in scoped_sessions if s.live and not s.is_requester
+        s for s in session_impacts if s.live and not s.is_requester
     ]
-    disruptive_leases = [l for l in scoped_leases if l.disruptive]
+    disruptive_leases = [l for l in lease_impacts if l.disruptive]
-    critical_sections = [l for l in scoped_leases if l.is_critical_section]
+    critical_sections = [l for l in lease_impacts if l.is_critical_section]
-    mutations = [l for l in scoped_leases if l.is_mutation]
+    mutations = [l for l in lease_impacts if l.is_mutation]
-    terminal_lock_in_scope = (
-        terminal_lock
-        if resolved_class
-        not in {
-            RestartClass.CLIENT_RECONNECT,
-            RestartClass.SESSION_RECONNECT,
-        }
-        else None
-    )
 
     affected_issues = sorted(
         {
@@ -672,24 +348,9 @@ def evaluate_restart_impact(
         }
     )
 
-    disruptive = bool(
+    disruptive = bool(disruptive_leases or other_live_sessions or terminal_lock)
-        disruptive_leases or other_live_sessions or terminal_lock_in_scope
-    )
 
-    authorization_ok = bool(
+    if not inventory_complete:
-        not unknown_class
-        and permission_authorized
-        and role_authorized
-        and approval_satisfied
-        and target_complete
-    )
-
-    if policy_enforced and not authorization_ok:
-        verdict = VERDICT_UNSAFE
-        allow_restart = False
-        reasons.append("restart class authorization denied (fail closed)")
-        reasons.extend(authorization_reasons)
-    elif not inventory_complete:
         verdict = VERDICT_UNSAFE
         allow_restart = False
         reasons.append(
@@ -720,7 +381,7 @@ def evaluate_restart_impact(
             f"{len(critical_sections)} critical section(s) in flight "
             "(active lease with a live owner)"
         )
-    if terminal_lock_in_scope:
+    if terminal_lock:
         reasons.append("active terminal (merge) lock present")
 
     override_would_allow = bool(inventory_complete and disruptive)
@@ -750,12 +411,6 @@ def evaluate_restart_impact(
     audit_record = {
         "event": "restart_impact_evaluated",
         "coordinator_version": COORDINATOR_VERSION,
-        "restart_class": (
-            resolved_class.value if resolved_class else str(restart_class or "")
-        ),
-        "required_permission": (
-            policy.required_permission if policy is not None else None
-        ),
         "evaluated_at": moment.isoformat(),
         "dry_run": dry_run,
         "operator_override": bool(operator_override),
@@ -769,15 +424,6 @@ def evaluate_restart_impact(
 
     return RestartImpactReport(
         coordinator_version=COORDINATOR_VERSION,
-        restart_class=(
-            resolved_class.value if resolved_class else str(restart_class or "")
-        ),
-        restart_policy=policy.as_dict() if policy is not None else {},
-        policy_enforced=policy_enforced,
-        permission_authorized=permission_authorized,
-        role_authorized=role_authorized,
-        approval_satisfied=approval_satisfied,
-        authorization_reasons=authorization_reasons,
         evaluated_at=moment.isoformat(),
         dry_run=dry_run,
         restart_performed=False,
@@ -794,11 +440,9 @@ def evaluate_restart_impact(
         affected_issues=affected_issues,
         affected_prs=affected_prs,
         mutations=mutations,
-        terminal_lock=(
+        terminal_lock=dict(terminal_lock)
-            dict(terminal_lock_in_scope)
+        if isinstance(terminal_lock, Mapping)
-            if isinstance(terminal_lock_in_scope, Mapping)
+        else terminal_lock,
-            else terminal_lock_in_scope
-        ),
         ack_state=ack_state,
         prior_recovery_attempts=prior_recovery_attempts,
         counts=counts,

tests/test_restart_classes.py

@@ -1,232 +0,0 @@
-"""Permission, drain, routing, and audit matrix for restart classes (#663)."""
-
-from __future__ import annotations
-
-import os
-from datetime import datetime, timezone
-
-import restart_coordinator as rc
-
-NOW = datetime(2026, 7, 24, 20, 0, tzinfo=timezone.utc)
-
-
-def _inventory() -> dict:
-    return {
-        "inventory_complete": True,
-        "sessions": [
-            {
-                "session_id": "requester",
-                "role": "author",
-                "profile": "prgs-author",
-                "pid": os.getpid(),
-                "status": "active",
-                "last_heartbeat_at": NOW.isoformat(),
-            },
-            {
-                "session_id": "reviewer",
-                "role": "reviewer",
-                "profile": "prgs-reviewer",
-                "pid": os.getpid(),
-                "status": "active",
-                "last_heartbeat_at": NOW.isoformat(),
-            },
-        ],
-        "leases": [
-            {
-                "lease_id": "review-lease",
-                "session_id": "reviewer",
-                "role": "reviewer",
-                "phase": "reviewing",
-                "work_kind": "pr",
-                "work_number": 900,
-                "worktree_path": "/tmp/review-900",
-                "freshness": {"freshness": "active"},
-            }
-        ],
-    }
-
-
-def _evaluate(
-    restart_class: rc.RestartClass,
-    *,
-    role: str = "controller",
-    permissions: tuple[str, ...] | None = None,
-    approved: bool = True,
-    operator: bool = True,
-    **targets,
-):
-    return rc.evaluate_restart_impact(
-        _inventory(),
-        now=NOW,
-        requesting_session_id="requester",
-        restart_class=restart_class,
-        requester_role=role,
-        requester_permissions=(
-            permissions if permissions is not None
-            else rc.permissions_for_role(role)
-        ),
-        controller_approved=approved,
-        operator_authorized=operator,
-        **targets,
-    )
-
-
-def test_policy_table_covers_exactly_all_nine_classes():
-    assert set(rc.RESTART_CLASS_POLICIES) == set(rc.RestartClass)
-    assert len(rc.RESTART_CLASS_POLICIES) == 9
-    for restart_class, policy in rc.RESTART_CLASS_POLICIES.items():
-        assert policy.restart_class is restart_class
-        assert policy.required_permission
-        assert policy.expected_blast_radius in {
-            rc.BLAST_NONE, rc.BLAST_LOW, rc.BLAST_MEDIUM, rc.BLAST_HIGH
-        }
-        assert policy.drain_requirement
-        assert policy.approval_requirement
-        assert policy.audit_requirement
-        assert policy.recovery_behavior
-
-
-def test_permission_matrix_allows_each_class_with_exact_permission():
-    targets = {
-        rc.RestartClass.WORKER_RESTART: {"target_session_id": "reviewer"},
-        rc.RestartClass.ROLE_RUNTIME_RESTART: {"target_role": "reviewer"},
-        rc.RestartClass.CONNECTOR_RESTART: {"target_connector": "github"},
-    }
-    for restart_class, policy in rc.RESTART_CLASS_POLICIES.items():
-        report = _evaluate(
-            restart_class,
-            permissions=(policy.required_permission,),
-            **targets.get(restart_class, {}),
-        )
-        assert report.permission_authorized, restart_class
-        assert report.role_authorized, restart_class
-        assert report.approval_satisfied, restart_class
-        assert report.audit_record["restart_class"] == restart_class.value
-        assert (
-            report.audit_record["required_permission"]
-            == policy.required_permission
-        )
-
-
-def test_missing_or_nearby_permission_denies():
-    report = _evaluate(
-        rc.RestartClass.ROLE_RUNTIME_RESTART,
-        permissions=("mcp.restart.worker.request",),
-        target_role="reviewer",
-    )
-    assert report.verdict == rc.VERDICT_UNSAFE
-    assert not report.allow_restart
-    assert not report.permission_authorized
-    assert any("missing required permission" in r for r in report.reasons)
-
-
-def test_unknown_restart_class_denies_fail_closed():
-    report = rc.evaluate_restart_impact(
-        _inventory(),
-        now=NOW,
-        restart_class="surprise_reboot",
-        requester_role="admin",
-        requester_permissions=("mcp.restart.host.request",),
-        controller_approved=True,
-        operator_authorized=True,
-    )
-    assert report.verdict == rc.VERDICT_UNSAFE
-    assert not report.allow_restart
-    assert report.restart_policy == {}
-    assert any("unknown restart class" in r for r in report.reasons)
-
-
-def test_worker_roles_cannot_request_full_or_host_restart():
-    for role in rc.WORKER_ROLES:
-        granted = rc.permissions_for_role(role)
-        assert "mcp.restart.full.request" not in granted
-        assert "mcp.restart.host.request" not in granted
-        report = _evaluate(
-            rc.RestartClass.FULL_MCP_RESTART,
-            role=role,
-            permissions=granted,
-        )
-        assert not report.role_authorized
-        assert not report.allow_restart
-
-
-def test_controller_approval_is_independent_of_permission():
-    report = _evaluate(
-        rc.RestartClass.WORKER_RESTART,
-        approved=False,
-        target_session_id="reviewer",
-    )
-    assert report.permission_authorized
-    assert not report.approval_satisfied
-    assert not report.allow_restart
-
-
-def test_narrow_classes_do_not_inherit_full_drain_or_peer_lease_block():
-    for restart_class in (
-        rc.RestartClass.CLIENT_RECONNECT,
-        rc.RestartClass.SESSION_RECONNECT,
-        rc.RestartClass.CONFIGURATION_RELOAD,
-    ):
-        report = _evaluate(restart_class)
-        assert not report.restart_policy["full_drain_required"]
-        assert report.counts["leases_disruptive"] == 0
-        assert report.counts["sessions_live_other"] == 0
-        assert report.counts["critical_sections"] == 0
-        assert report.counts["mutations"] == 0
-        assert report.allow_restart, (restart_class, report.reasons)
-
-
-def test_client_reconnect_does_not_wait_for_unrelated_terminal_lock():
-    inventory = _inventory()
-    inventory["terminal_lock"] = {"terminal_pr": 901}
-    report = rc.evaluate_restart_impact(
-        inventory,
-        now=NOW,
-        requesting_session_id="requester",
-        restart_class=rc.RestartClass.CLIENT_RECONNECT,
-        requester_role="author",
-        requester_permissions=rc.permissions_for_role("author"),
-    )
-    assert report.allow_restart
-    assert report.terminal_lock is None
-
-
-def test_scoped_restart_only_counts_named_target():
-    report = _evaluate(
-        rc.RestartClass.ROLE_RUNTIME_RESTART,
-        target_role="author",
-    )
-    assert report.counts["leases_disruptive"] == 0
-    assert report.affected_prs == []
-    assert report.allow_restart
-
-    reviewer = _evaluate(
-        rc.RestartClass.ROLE_RUNTIME_RESTART,
-        target_role="reviewer",
-    )
-    assert reviewer.counts["leases_disruptive"] == 1
-    assert reviewer.affected_prs == [900]
-    assert not reviewer.allow_restart
-
-
-def test_missing_scoped_target_denies_instead_of_widening():
-    for restart_class in (
-        rc.RestartClass.WORKER_RESTART,
-        rc.RestartClass.ROLE_RUNTIME_RESTART,
-        rc.RestartClass.CONNECTOR_RESTART,
-    ):
-        report = _evaluate(restart_class)
-        assert not report.allow_restart
-        assert any("target required" in r for r in report.reasons)
-
-
-def test_only_full_and_host_classes_require_full_drain():
-    requiring_full = {
-        restart_class
-        for restart_class, policy in rc.RESTART_CLASS_POLICIES.items()
-        if policy.full_drain_required
-    }
-    assert requiring_full == {
-        rc.RestartClass.FULL_MCP_RESTART,
-        rc.RestartClass.HOST_RESTART,
-    }

tests/test_webui_sanctioned_restart.py

@@ -444,12 +444,6 @@ class TestAuditEmission(unittest.TestCase):
         )
         self.assertEqual(record["target"]["namespace"], NAMESPACE)
         self.assertEqual(record["target"]["mode"], "restart")
-        self.assertEqual(
-            record["target"]["restart_class"], "role_runtime_restart"
-        )
-        self.assertEqual(
-            record["metadata"]["restart_class"], "role_runtime_restart"
-        )
         self.assertEqual(record["result"], console_audit.RESULT_ALLOWED)
         self.assertEqual(record["actor"]["subject"], "[email protected]")
         self.assertFalse(record["metadata"]["process_kill_executed"])

tests/test_webui_sessions_view.py

@@ -0,0 +1,457 @@
+"""Tests for the Runtime and session view (Phase 1, #641).
+
+Covers clean and stale session rendering, contamination marker surfacing,
+worktree binding display, sanctioned recovery links (no pkill), nav/live
+status, and the JSON API export.
+"""
+
+from __future__ import annotations
+
+import sys
+import unittest
+from pathlib import Path
+from unittest import mock
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+
+from tests.webui_testclient import TestClient
+
+from webui.app import create_app
+from webui.inventory import (
+    AUTHORITY_CONTROL_PLANE_DB,
+    AUTHORITY_FILESYSTEM,
+    InventorySection,
+    InventorySnapshot,
+    STATUS_OK,
+    STATUS_UNAVAILABLE,
+)
+from webui.nav import NAV_GROUPS, STUB_PAGES, iter_nav_items
+from webui.runtime_health import FileHash, RuntimeSnapshot
+from webui.session_loader import (
+    ContaminationMarker,
+    SessionRow,
+    SessionViewSnapshot,
+    _build_session_rows,
+    load_session_view_snapshot,
+    snapshot_to_dict,
+)
+from webui.session_views import render_sessions_page
+
+
+def _runtime(
+    *,
+    stale: str | None = None,
+    profile: str = "prgs-author",
+    role: str = "author",
+) -> RuntimeSnapshot:
+    return RuntimeSnapshot(
+        project_id="gitea-tools",
+        repo_root="/tmp/repo",
+        remote="prgs",
+        host="gitea.prgs.cc",
+        profile_name=profile,
+        role_kind=role,
+        config_model="v2-contexts",
+        profile_mode="dynamic-profile",
+        profile_source="config file profile",
+        authenticated_username="jcwalker3",
+        identity_error=None,
+        repo_sha="a" * 40,
+        remote_master_sha="a" * 40,
+        commits_behind_master=0,
+        stale_runtime_warning=stale,
+        shell_health={"shell_use_allowed": True, "consecutive_spawn_failures": 0},
+        workflow_hashes=(
+            FileHash(label="SKILL.md", path="skills/llm-project-workflow/SKILL.md", sha256="abc"),
+        ),
+        schema_hashes=(),
+        restart_guidance="docs/mcp-namespace-eof-recovery.md",
+        fetch_error=None,
+    )
+
+
+def _inventory(
+    *,
+    sessions: tuple[dict, ...] = (),
+    leases: tuple[dict, ...] = (),
+    locks: tuple[dict, ...] = (),
+    worktrees: tuple[dict, ...] = (),
+    namespaces: tuple[dict, ...] = (),
+) -> InventorySnapshot:
+    sections = (
+        InventorySection(
+            name="sessions",
+            authority=AUTHORITY_CONTROL_PLANE_DB,
+            status=STATUS_OK,
+            items=sessions,
+        ),
+        InventorySection(
+            name="leases",
+            authority=AUTHORITY_CONTROL_PLANE_DB,
+            status=STATUS_OK,
+            items=leases,
+        ),
+        InventorySection(
+            name="locks",
+            authority=AUTHORITY_FILESYSTEM,
+            status=STATUS_OK,
+            items=locks,
+        ),
+        InventorySection(
+            name="worktrees",
+            authority=AUTHORITY_FILESYSTEM,
+            status=STATUS_OK,
+            items=worktrees,
+        ),
+        InventorySection(
+            name="namespaces",
+            authority=AUTHORITY_FILESYSTEM,
+            status=STATUS_OK,
+            items=namespaces
+            or (
+                {
+                    "profile_name": "prgs-author",
+                    "role": "author",
+                    "mcp_namespace": "gitea-author",
+                    "capability_summary": {
+                        "can_author": True,
+                        "can_review": False,
+                        "can_merge": False,
+                    },
+                    "active": True,
+                },
+            ),
+            reason="only the profile serving this web process is observable",
+        ),
+    )
+    index = {section.name: section for section in sections}
+    return InventorySnapshot(
+        generated_at="2026-07-25T00:00:00+00:00",
+        sections=sections,
+        collisions=(),
+        correlations=(),
+        scan_ms=1.0,
+        _section_index=index,
+    )
+
+
+def _clean_session() -> dict:
+    return {
+        "session_id": "prgs-author-111-clean",
+        "role": "author",
+        "profile": "prgs-author",
+        "namespace": "gitea-author",
+        "pid": 1111,
+        "pid_alive": True,
+        "status": "active",
+        "started_at": "2026-07-25T00:00:00Z",
+        "last_heartbeat_at": "2026-07-25T01:00:00Z",
+    }
+
+
+def _stale_session() -> dict:
+    return {
+        "session_id": "prgs-author-222-stale",
+        "role": "author",
+        "profile": "prgs-author",
+        "namespace": "gitea-author",
+        "pid": 2222,
+        "pid_alive": False,
+        "status": "active",
+        "started_at": "2026-07-24T00:00:00Z",
+        "last_heartbeat_at": "2026-07-24T01:00:00Z",
+    }
+
+
+class TestBuildSessionRows(unittest.TestCase):
+    def test_clean_session_has_no_stale_or_contamination_flags(self):
+        inventory = _inventory(
+            sessions=(_clean_session(),),
+            leases=(
+                {
+                    "lease_id": "lease-clean",
+                    "session_id": "prgs-author-111-clean",
+                    "status": "active",
+                    "expired": False,
+                    "work_kind": "issue",
+                    "work_number": 641,
+                },
+            ),
+            locks=(
+                {
+                    "issue_number": 641,
+                    "branch_name": "feat/issue-641-runtime-session-view",
+                    "worktree_path": "~/Development/Gitea-Tools/branches/feat-issue-641",
+                    "live": True,
+                },
+            ),
+        )
+        rows = _build_session_rows(inventory, contamination=())
+        self.assertEqual(len(rows), 1)
+        row = rows[0]
+        self.assertEqual(row.session_id, "prgs-author-111-clean")
+        self.assertEqual(row.role, "author")
+        self.assertEqual(row.namespace, "gitea-author")
+        self.assertEqual(row.pid_alive, True)
+        self.assertEqual(row.lease_ids, ("lease-clean",))
+        self.assertEqual(row.work_refs, ("issue#641",))
+        self.assertTrue(row.worktree_paths)
+        self.assertEqual(row.stale_flags, ())
+        self.assertEqual(row.contamination_flags, ())
+
+    def test_stale_session_flags_dead_pid(self):
+        inventory = _inventory(sessions=(_stale_session(),))
+        rows = _build_session_rows(inventory, contamination=())
+        self.assertEqual(rows[0].stale_flags, ("pid-dead",))
+
+    def test_contamination_marker_binds_to_session(self):
+        inventory = _inventory(sessions=(_clean_session(),))
+        marker = ContaminationMarker(
+            kind="runtime_recovery_contamination",
+            on_disk=True,
+            has_payload=True,
+            summary="manual daemon kill",
+            reason_class="manual_daemon_kill",
+            session_id="prgs-author-111-clean",
+            role="author",
+            command_summary="pkill -f mcp_server.py",
+            cleared=False,
+        )
+        rows = _build_session_rows(inventory, contamination=(marker,))
+        self.assertIn("runtime_recovery_contamination", rows[0].contamination_flags)
+
+    def test_process_wide_contamination_surfaces_on_all_sessions(self):
+        inventory = _inventory(sessions=(_clean_session(), _stale_session()))
+        marker = ContaminationMarker(
+            kind="stable_branch_contamination",
+            on_disk=True,
+            has_payload=True,
+            summary="direct master push attempt",
+            reason_class="stable_branch_push",
+            session_id=None,
+            cleared=False,
+        )
+        rows = _build_session_rows(inventory, contamination=(marker,))
+        self.assertEqual(len(rows), 2)
+        for row in rows:
+            self.assertTrue(
+                any("stable_branch_contamination" in f for f in row.contamination_flags)
+            )
+
+
+class TestRenderSessionsPage(unittest.TestCase):
+    def _snapshot(
+        self,
+        *,
+        sessions: tuple[dict, ...],
+        contamination: tuple[ContaminationMarker, ...] = (),
+        stale_runtime: str | None = None,
+    ) -> SessionViewSnapshot:
+        inventory = _inventory(
+            sessions=sessions,
+            leases=(
+                {
+                    "lease_id": "lease-1",
+                    "session_id": sessions[0]["session_id"] if sessions else "",
+                    "status": "active",
+                    "expired": False,
+                    "work_kind": "issue",
+                    "work_number": 641,
+                },
+            )
+            if sessions
+            else (),
+            locks=(
+                {
+                    "issue_number": 641,
+                    "worktree_path": "branches/feat-issue-641",
+                },
+            )
+            if sessions
+            else (),
+            worktrees=(
+                {
+                    "rel_path": "branches/feat-issue-641",
+                    "branch": "feat/issue-641-runtime-session-view",
+                    "classification": "active_issue_work",
+                    "registered_worktree": True,
+                    "dirty": False,
+                },
+            ),
+        )
+        rows = _build_session_rows(inventory, contamination)
+        return SessionViewSnapshot(
+            runtime=_runtime(stale=stale_runtime),
+            inventory=inventory,
+            sessions=rows,
+            contamination_markers=contamination,
+        )
+
+    def test_clean_session_render(self):
+        html = render_sessions_page(self._snapshot(sessions=(_clean_session(),)))
+        self.assertIn("Runtime and sessions", html)
+        self.assertIn("prgs-author-111-clean", html)
+        self.assertIn("gitea-author", html)
+        self.assertIn("branches/feat-issue-641", html)
+        self.assertIn("Sanctioned recovery", html)
+        self.assertIn("docs/mcp-namespace-eof-recovery.md", html)
+        # Recovery section must name reconnect and forbid manual kill.
+        recovery_idx = html.lower().find("sanctioned recovery")
+        self.assertGreaterEqual(recovery_idx, 0)
+        recovery = html[recovery_idx:].lower()
+        self.assertIn("reconnect", recovery)
+        self.assertIn("contamination", recovery)
+        self.assertIn("not recovery", recovery)
+        self.assertNotIn("run pkill", recovery)
+        self.assertNotIn("killall", recovery)
+
+    def test_stale_session_render(self):
+        html = render_sessions_page(self._snapshot(sessions=(_stale_session(),)))
+        self.assertIn("prgs-author-222-stale", html)
+        self.assertIn("pid-dead", html)
+        self.assertIn("badge-stale", html)
+
+    def test_contamination_render_is_not_silent(self):
+        marker = ContaminationMarker(
+            kind="runtime_recovery_contamination",
+            on_disk=True,
+            has_payload=True,
+            summary="manual kill",
+            reason_class="manual_daemon_kill",
+            session_id="prgs-author-111-clean",
+            command_summary="pkill -f mcp_server.py",
+            cleared=False,
+        )
+        html = render_sessions_page(
+            self._snapshot(sessions=(_clean_session(),), contamination=(marker,))
+        )
+        self.assertIn("Contamination markers", html)
+        self.assertIn("runtime_recovery_contamination", html)
+        self.assertIn("ACTIVE", html)
+        self.assertIn("badge-blocked", html)
+
+    def test_stale_runtime_banner(self):
+        html = render_sessions_page(
+            self._snapshot(
+                sessions=(_clean_session(),),
+                stale_runtime="server behind master by 3 commits",
+            )
+        )
+        self.assertIn("Stale runtime", html)
+        self.assertIn("server behind master", html)
+
+
+class TestSessionLoaderComposition(unittest.TestCase):
+    def test_load_with_injected_sources(self):
+        inventory = _inventory(sessions=(_clean_session(), _stale_session()))
+        snap = load_session_view_snapshot(
+            load_runtime=lambda: _runtime(),
+            load_inventory=lambda: inventory,
+            inspect_contamination=lambda **_k: {
+                "on_disk": False,
+                "has_payload": False,
+                "summary": "absent",
+            },
+            load_contamination_payload=lambda **_k: None,
+        )
+        self.assertEqual(len(snap.sessions), 2)
+        self.assertEqual(snap.stale_session_count, 1)
+        self.assertEqual(snap.contaminated_session_count, 0)
+        data = snapshot_to_dict(snap)
+        self.assertEqual(data["view"], "runtime-sessions")
+        self.assertEqual(data["issue"], 641)
+        self.assertTrue(data["read_only"])
+        self.assertEqual(data["session_counts"]["total"], 2)
+        self.assertEqual(data["session_counts"]["stale"], 1)
+        self.assertIn("recovery_docs", data)
+
+
+class TestSessionsRoutes(unittest.TestCase):
+    def setUp(self):
+        self.client = TestClient(create_app())
+        inventory = _inventory(
+            sessions=(_clean_session(), _stale_session()),
+            leases=(
+                {
+                    "lease_id": "lease-x",
+                    "session_id": "prgs-author-111-clean",
+                    "status": "active",
+                    "expired": False,
+                    "work_kind": "issue",
+                    "work_number": 641,
+                },
+            ),
+            locks=(
+                {
+                    "issue_number": 641,
+                    "worktree_path": "branches/feat-issue-641",
+                },
+            ),
+            worktrees=(
+                {
+                    "rel_path": "branches/feat-issue-641",
+                    "branch": "feat/issue-641-runtime-session-view",
+                    "classification": "active_issue_work",
+                    "registered_worktree": True,
+                    "dirty": False,
+                },
+            ),
+        )
+        rows = _build_session_rows(inventory, contamination=())
+        self.snapshot = SessionViewSnapshot(
+            runtime=_runtime(stale="stale for test"),
+            inventory=inventory,
+            sessions=rows,
+            contamination_markers=(),
+        )
+        self._patch = mock.patch(
+            "webui.app.load_session_view_snapshot",
+            return_value=self.snapshot,
+        )
+        self._patch.start()
+
+    def tearDown(self):
+        self._patch.stop()
+
+    def test_sessions_page_live(self):
+        response = self.client.get("/sessions")
+        self.assertEqual(response.status_code, 200)
+        self.assertIn("Runtime and sessions", response.text)
+        self.assertIn("prgs-author-111-clean", response.text)
+        self.assertIn("prgs-author-222-stale", response.text)
+        self.assertIn("pid-dead", response.text)
+        self.assertIn("Sanctioned recovery", response.text)
+        self.assertNotIn("Phase 1 shell placeholder", response.text)
+        self.assertNotIn("child issue of #425", response.text.lower())
+
+    def test_api_sessions_json(self):
+        for path in ("/api/sessions", "/api/v1/sessions"):
+            response = self.client.get(path)
+            self.assertEqual(response.status_code, 200, path)
+            data = response.json()
+            self.assertEqual(data["view"], "runtime-sessions")
+            self.assertEqual(data["session_counts"]["total"], 2)
+            self.assertEqual(data["session_counts"]["stale"], 1)
+            self.assertTrue(data["read_only"])
+            self.assertEqual(data["mutations"], [])
+
+    def test_nav_marks_sessions_live(self):
+        sessions_items = [
+            item for item in iter_nav_items() if item.href == "/sessions"
+        ]
+        self.assertEqual(len(sessions_items), 1)
+        self.assertEqual(sessions_items[0].status, "live")
+        self.assertNotIn("/sessions", STUB_PAGES)
+        # Home page should not mark Sessions as stub.
+        home = self.client.get("/")
+        self.assertEqual(home.status_code, 200)
+        self.assertIn('href="/sessions"', home.text)
+        # Stub marker only appears next to remaining stub destinations.
+        self.assertNotIn(
+            'href="/sessions">Sessions</a> <span class="muted">(stub)</span>',
+            home.text,
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

webui/app.py

@@ -48,6 +48,11 @@ 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.session_loader import (
+    load_session_view_snapshot,
+    snapshot_to_dict as session_view_snapshot_to_dict,
+)
+from webui.session_views import render_sessions_page
 from webui.inventory import (
     SECTION_NAMES as _INVENTORY_SECTIONS,
     load_inventory_snapshot,
@@ -87,6 +92,7 @@ _LEGACY_PAGES = (
     ("/projects", "Projects", "registry and onboarding (#427)"),
     ("/prompts", "Prompts", "canonical workflow prompt library (#428)"),
     ("/runtime", "Runtime", "MCP health and stale-runtime detection (#430)"),
+    ("/sessions", "Sessions", "runtime and session view (#641)"),
     ("/audit", "Audit", "final-report paste and validator preview (#431)"),
     ("/worktrees", "Worktrees", "branch hygiene dashboard (#432)"),
     ("/leases", "Leases", "collision and lease visibility (#433)"),
@@ -325,6 +331,17 @@ async def api_runtime(_request: Request) -> JSONResponse:
     return JSONResponse(runtime_snapshot_to_dict(load_runtime_snapshot()))
 
 
+async def sessions(_request: Request) -> HTMLResponse:
+    """Runtime and session view (#641) — read-only composition of health + inventory."""
+    snapshot = load_session_view_snapshot()
+    return HTMLResponse(render_sessions_page(snapshot))
+
+
+async def api_sessions(_request: Request) -> JSONResponse:
+    """JSON export for the runtime/session view (#641)."""
+    return JSONResponse(session_view_snapshot_to_dict(load_session_view_snapshot()))
+
+
 async def _parse_audit_form(request: Request) -> tuple[str, str | None]:
     if request.method == "GET":
         return "", None
@@ -764,6 +781,9 @@ 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("/sessions", sessions, methods=["GET"]),
+            Route("/api/sessions", api_sessions, methods=["GET"]),
+            Route("/api/v1/sessions", api_sessions, methods=["GET"]),
             Route("/api/v1/timeline", api_v1_timeline, methods=["GET"]),
             Route("/analytics", analytics, methods=["GET"]),
             Route("/api/analytics", api_v1_analytics, methods=["GET"]),

webui/nav.py

@@ -48,7 +48,7 @@ NAV_GROUPS: tuple[NavGroup, ...] = (
     )),
     NavGroup("Runtime/Sessions", (
         NavItem("/runtime", "Runtime health"),
-        NavItem("/sessions", "Sessions", "stub"),
+        NavItem("/sessions", "Sessions"),
     )),
     NavGroup("Projects", (
         NavItem("/projects", "Projects"),
@@ -76,11 +76,6 @@ NAV_GROUPS: tuple[NavGroup, ...] = (
 # 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. "

webui/runtime_views.py

@@ -88,5 +88,7 @@ def render_runtime_page(snapshot: RuntimeSnapshot) -> str:
         "<p class='muted'>MVP is read-only — restart MCP servers from your IDE/operator "
         "workflow. Related issue: <code>#420</code>. Guidance: "
         f"<code>{html.escape(snapshot.restart_guidance)}</code></p>"
-        "<p class='muted'>This page does not expose tokens or perform MCP restarts.</p>"
+        "<p class='muted'>This page does not expose tokens or perform MCP restarts. "
+        "Correlated sessions, worktree bindings, and contamination markers: "
+        "<a href='/sessions'>/sessions</a> (#641).</p>"
     )

webui/sanctioned_restart.py

@@ -38,7 +38,6 @@ from dataclasses import asdict, dataclass
 from typing import Any
 
 import mcp_namespace_health
-import restart_coordinator
 import runtime_recovery_guard
 from webui import console_audit, console_authz
 
@@ -100,14 +99,6 @@ def _clean(value: Any) -> str:
     return str(value or "").strip()
 
 
-def restart_class_for_mode(mode: str) -> str:
-    """Map the existing namespace controls onto the #663 class taxonomy."""
-
-    if _clean(mode) == MODE_RELOAD:
-        return restart_coordinator.RestartClass.CONFIGURATION_RELOAD.value
-    return restart_coordinator.RestartClass.ROLE_RUNTIME_RESTART.value
-
-
 # --- Mutation ledger --------------------------------------------------------
 
 
@@ -265,7 +256,6 @@ def build_restart_preview(
 
     return {
         "action_id": action_id,
-        "restart_class": restart_class_for_mode(md),
         "namespace": ns,
         "mode": md,
         "scope_valid": scope_error is None,
@@ -319,7 +309,6 @@ def assess_restart_request(
             "reason_code": reason_code,
             "detail": detail,
             "action_id": action_id,
-            "restart_class": restart_class_for_mode(md),
             "namespace": ns,
             "mode": md,
             "preview": preview,
@@ -404,7 +393,6 @@ def assess_restart_request(
             "process."
         ),
         "action_id": action_id,
-        "restart_class": restart_class_for_mode(md),
         "namespace": ns,
         "mode": md,
         "preview": preview,
@@ -453,11 +441,7 @@ def execute_restart(
             else console_audit.RESULT_DENIED
         ),
         principal=principal,
-        target={
+        target={"namespace": assessment["namespace"], "mode": assessment["mode"]},
-            "namespace": assessment["namespace"],
-            "mode": assessment["mode"],
-            "restart_class": assessment["restart_class"],
-        },
         reason_code=assessment["reason_code"],
         detail=assessment["detail"],
         request_id=request_id,
@@ -466,7 +450,6 @@ def execute_restart(
             "gates_passed": assessment["gates_passed"],
             "process_kill_executed": False,
             "post_restart_verification_required": True,
-            "restart_class": assessment["restart_class"],
         },
     )
 
@@ -480,7 +463,6 @@ def execute_restart(
         "namespace": assessment["namespace"],
         "mode": assessment["mode"],
         "action_id": action_id,
-        "restart_class": assessment["restart_class"],
         "process_kill_executed": False,
         "host_hook": assessment["preview"]["restart_hook"],
         "next_action": (

webui/session_loader.py

@@ -0,0 +1,428 @@
+"""Compose runtime health + inventory into a sessions/runtime view (#641).
+
+Phase 1 is read-only. It correlates namespaces, sessions, capabilities,
+worktree bindings, lease ownership, stale flags, and contamination markers
+when they are detectable on disk (#630 / #671). It never restarts, kills, or
+takes over a session.
+
+Sources:
+
+* :mod:`webui.runtime_health` — profile, role, stale runtime, shell health.
+* :mod:`webui.inventory` — sessions, leases, locks, worktrees, namespaces
+  and collision signals from the control-plane DB + filesystem.
+* :mod:`mcp_session_state` — durable contamination markers (inspect only).
+
+Secrets are never read. Absolute paths are collapsed by inventory redaction.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import Any, Callable
+
+import mcp_session_state
+from webui.inventory import (
+    InventorySnapshot,
+    load_inventory_snapshot,
+    snapshot_to_dict as inventory_snapshot_to_dict,
+)
+from webui.runtime_health import (
+    RuntimeSnapshot,
+    load_runtime_snapshot,
+    snapshot_to_dict as runtime_snapshot_to_dict,
+)
+
+# Sanctioned recovery pointers only — never pkill / killall (#630).
+SANCTIONED_RECOVERY_DOCS: tuple[dict[str, str], ...] = (
+    {
+        "label": "MCP namespace EOF recovery (reconnect only)",
+        "path": "docs/mcp-namespace-eof-recovery.md",
+        "note": "IDE/client reconnect or operator-owned restart; never kill daemons.",
+    },
+    {
+        "label": "MCP namespace health",
+        "path": "docs/mcp-namespace-health.md",
+        "note": "client_namespace probe proves namespace health.",
+    },
+    {
+        "label": "Restart path inventory",
+        "path": "docs/mcp-restart-path-inventory.md",
+        "note": "Catalog of sanctioned reconnect/restart paths.",
+    },
+    {
+        "label": "Local web UI recovery",
+        "path": "docs/webui-local-dev.md",
+        "note": "Operator console start and documented recovery sequence.",
+    },
+)
+
+_CONTAMINATION_KINDS: tuple[str, ...] = (
+    mcp_session_state.KIND_RUNTIME_RECOVERY_CONTAMINATION,
+    mcp_session_state.KIND_STABLE_BRANCH_CONTAMINATION,
+)
+
+
+@dataclass(frozen=True)
+class ContaminationMarker:
+    """A detectable durable contamination marker (audit-safe summary)."""
+
+    kind: str
+    on_disk: bool
+    has_payload: bool
+    summary: str
+    reason_class: str | None = None
+    session_id: str | None = None
+    role: str | None = None
+    command_summary: str | None = None
+    cleared: bool = False
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "kind": self.kind,
+            "on_disk": self.on_disk,
+            "has_payload": self.has_payload,
+            "summary": self.summary,
+            "reason_class": self.reason_class,
+            "session_id": self.session_id,
+            "role": self.role,
+            "command_summary": self.command_summary,
+            "cleared": self.cleared,
+            "active": self.on_disk and self.has_payload and not self.cleared,
+        }
+
+
+@dataclass(frozen=True)
+class SessionRow:
+    """One correlated session row for the sessions table."""
+
+    session_id: str
+    role: str | None
+    profile: str | None
+    namespace: str | None
+    pid: int | None
+    pid_alive: bool | None
+    status: str | None
+    started_at: str | None
+    last_heartbeat_at: str | None
+    lease_ids: tuple[str, ...] = ()
+    work_refs: tuple[str, ...] = ()
+    worktree_paths: tuple[str, ...] = ()
+    stale_flags: tuple[str, ...] = ()
+    contamination_flags: tuple[str, ...] = ()
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "session_id": self.session_id,
+            "role": self.role,
+            "profile": self.profile,
+            "namespace": self.namespace,
+            "pid": self.pid,
+            "pid_alive": self.pid_alive,
+            "status": self.status,
+            "started_at": self.started_at,
+            "last_heartbeat_at": self.last_heartbeat_at,
+            "lease_ids": list(self.lease_ids),
+            "work_refs": list(self.work_refs),
+            "worktree_paths": list(self.worktree_paths),
+            "stale_flags": list(self.stale_flags),
+            "contamination_flags": list(self.contamination_flags),
+            "is_stale": bool(self.stale_flags),
+            "is_contaminated": bool(self.contamination_flags),
+        }
+
+
+@dataclass(frozen=True)
+class SessionViewSnapshot:
+    """Composed runtime + session inventory view (#641)."""
+
+    runtime: RuntimeSnapshot
+    inventory: InventorySnapshot
+    sessions: tuple[SessionRow, ...]
+    contamination_markers: tuple[ContaminationMarker, ...]
+    recovery_docs: tuple[dict[str, str], ...] = SANCTIONED_RECOVERY_DOCS
+    fetch_error: str | None = None
+
+    @property
+    def stale_session_count(self) -> int:
+        return sum(1 for row in self.sessions if row.stale_flags)
+
+    @property
+    def contaminated_session_count(self) -> int:
+        return sum(1 for row in self.sessions if row.contamination_flags)
+
+    @property
+    def active_contamination(self) -> tuple[ContaminationMarker, ...]:
+        return tuple(m for m in self.contamination_markers if m.to_dict()["active"])
+
+
+def _inspect_contamination(
+    kind: str,
+    *,
+    remote: str | None,
+    inspect: Callable[..., dict[str, Any]] | None = None,
+    load: Callable[..., dict[str, Any] | None] | None = None,
+) -> ContaminationMarker:
+    """Inspect one contamination kind; never raises into the page render path."""
+    inspect_fn = inspect or mcp_session_state.inspect_state_envelope
+    load_fn = load or mcp_session_state.load_state
+    try:
+        envelope = inspect_fn(kind=kind, remote=remote)
+    except Exception as exc:  # noqa: BLE001 — fail soft for the dashboard
+        return ContaminationMarker(
+            kind=kind,
+            on_disk=False,
+            has_payload=False,
+            summary=f"contamination inspect failed: {type(exc).__name__}",
+        )
+
+    reason_class = None
+    session_id = None
+    role = None
+    command_summary = None
+    cleared = False
+    summary = str(envelope.get("summary") or "")
+
+    if envelope.get("on_disk") and envelope.get("has_payload"):
+        try:
+            payload = load_fn(kind=kind, remote=remote) or {}
+        except Exception:  # noqa: BLE001
+            payload = {}
+        if isinstance(payload, dict):
+            reason_class = payload.get("reason_class")
+            session_id = payload.get("session_id")
+            role = payload.get("role")
+            command_summary = payload.get("command_summary") or payload.get("detail")
+            cleared = bool(payload.get("cleared_by_reconciler"))
+            if not summary:
+                summary = (
+                    f"{kind}: {reason_class or 'present'}"
+                    + (" (cleared)" if cleared else "")
+                )
+
+    return ContaminationMarker(
+        kind=kind,
+        on_disk=bool(envelope.get("on_disk")),
+        has_payload=bool(envelope.get("has_payload")),
+        summary=summary or f"{kind}: not present",
+        reason_class=str(reason_class) if reason_class else None,
+        session_id=str(session_id) if session_id else None,
+        role=str(role) if role else None,
+        command_summary=str(command_summary) if command_summary else None,
+        cleared=cleared,
+    )
+
+
+def _load_contamination_markers(
+    *,
+    remote: str | None,
+    inspect: Callable[..., dict[str, Any]] | None = None,
+    load: Callable[..., dict[str, Any] | None] | None = None,
+) -> tuple[ContaminationMarker, ...]:
+    return tuple(
+        _inspect_contamination(kind, remote=remote, inspect=inspect, load=load)
+        for kind in _CONTAMINATION_KINDS
+    )
+
+
+def _build_session_rows(
+    inventory: InventorySnapshot,
+    contamination: tuple[ContaminationMarker, ...],
+) -> tuple[SessionRow, ...]:
+    sessions_section = inventory.section("sessions")
+    leases_section = inventory.section("leases")
+    locks_section = inventory.section("locks")
+
+    leases_by_session: dict[str, list[dict[str, Any]]] = {}
+    for lease in (leases_section.items if leases_section else ()):
+        sid = str(lease.get("session_id") or "")
+        if sid:
+            leases_by_session.setdefault(sid, []).append(lease)
+
+    locks_by_session_hint: dict[str, list[dict[str, Any]]] = {}
+    for lock in (locks_section.items if locks_section else ()):
+        # Locks carry claimant profile/username, not control-plane session ids.
+        # Correlate later by matching lease work_number ↔ lock issue_number.
+        pass
+
+    active_markers = [m for m in contamination if m.to_dict()["active"]]
+    marker_session_ids = {
+        m.session_id for m in active_markers if m.session_id
+    }
+
+    rows: list[SessionRow] = []
+    for raw in sessions_section.items if sessions_section else ():
+        sid = str(raw.get("session_id") or "")
+        if not sid:
+            continue
+        session_leases = leases_by_session.get(sid, [])
+        lease_ids = tuple(
+            str(lease["lease_id"])
+            for lease in session_leases
+            if lease.get("lease_id")
+        )
+        work_refs: list[str] = []
+        work_numbers: list[int] = []
+        for lease in session_leases:
+            kind = lease.get("work_kind")
+            number = lease.get("work_number")
+            if kind and number is not None:
+                work_refs.append(f"{kind}#{number}")
+                try:
+                    work_numbers.append(int(number))
+                except (TypeError, ValueError):
+                    pass
+
+        worktree_paths: list[str] = []
+        for lock in (locks_section.items if locks_section else ()):
+            try:
+                issue_no = int(lock.get("issue_number"))
+            except (TypeError, ValueError):
+                continue
+            if issue_no in work_numbers and lock.get("worktree_path"):
+                worktree_paths.append(str(lock["worktree_path"]))
+
+        stale_flags: list[str] = []
+        if raw.get("pid_alive") is False:
+            stale_flags.append("pid-dead")
+        status = str(raw.get("status") or "").lower()
+        if status and status not in {"active", "alive", "running", "ok"}:
+            stale_flags.append(f"status:{status}")
+        for lease in session_leases:
+            if lease.get("expired") is True:
+                stale_flags.append("lease-expired")
+            if str(lease.get("status") or "").lower() == "active" and lease.get(
+                "expired"
+            ) is True:
+                stale_flags.append("active-lease-past-expiry")
+
+        contamination_flags: list[str] = []
+        if sid in marker_session_ids:
+            for marker in active_markers:
+                if marker.session_id == sid:
+                    contamination_flags.append(marker.kind)
+        # Process-wide contamination with no session binding still surfaces
+        # against every live session so it cannot be silent (#630).
+        for marker in active_markers:
+            if not marker.session_id and marker.kind not in contamination_flags:
+                contamination_flags.append(f"{marker.kind}:process-wide")
+
+        rows.append(
+            SessionRow(
+                session_id=sid,
+                role=raw.get("role"),
+                profile=raw.get("profile"),
+                namespace=raw.get("namespace"),
+                pid=raw.get("pid") if isinstance(raw.get("pid"), int) else None,
+                pid_alive=raw.get("pid_alive")
+                if isinstance(raw.get("pid_alive"), bool)
+                else None,
+                status=raw.get("status"),
+                started_at=raw.get("started_at"),
+                last_heartbeat_at=raw.get("last_heartbeat_at"),
+                lease_ids=lease_ids,
+                work_refs=tuple(work_refs),
+                worktree_paths=tuple(worktree_paths),
+                stale_flags=tuple(dict.fromkeys(stale_flags)),
+                contamination_flags=tuple(dict.fromkeys(contamination_flags)),
+            )
+        )
+
+    # Silence unused variable for the locks_by_session_hint placeholder path.
+    _ = locks_by_session_hint
+    return tuple(rows)
+
+
+def load_session_view_snapshot(
+    *,
+    load_runtime: Callable[..., RuntimeSnapshot] | None = None,
+    load_inventory: Callable[..., InventorySnapshot] | None = None,
+    inspect_contamination: Callable[..., dict[str, Any]] | None = None,
+    load_contamination_payload: Callable[..., dict[str, Any] | None] | None = None,
+) -> SessionViewSnapshot:
+    """Build the composed sessions/runtime view. Fail-soft on partial sources."""
+    runtime_loader = load_runtime or load_runtime_snapshot
+    inventory_loader = load_inventory or load_inventory_snapshot
+    fetch_error: str | None = None
+
+    try:
+        runtime = runtime_loader()
+    except Exception as exc:  # noqa: BLE001
+        fetch_error = f"runtime snapshot failed: {type(exc).__name__}: {exc}"
+        # Minimal placeholder so the page still renders inventory + recovery.
+        from webui.runtime_health import RuntimeSnapshot as _RS
+
+        runtime = _RS(
+            project_id="unknown",
+            repo_root="",
+            remote="",
+            host="",
+            profile_name="unknown",
+            role_kind="unknown",
+            config_model="unknown",
+            profile_mode="unknown",
+            profile_source="unknown",
+            authenticated_username=None,
+            identity_error=str(exc),
+            repo_sha=None,
+            remote_master_sha=None,
+            commits_behind_master=None,
+            stale_runtime_warning=None,
+            shell_health={},
+            workflow_hashes=(),
+            schema_hashes=(),
+            restart_guidance="docs/mcp-namespace-eof-recovery.md",
+            fetch_error=str(exc),
+        )
+
+    try:
+        inventory = inventory_loader()
+    except Exception as exc:  # noqa: BLE001
+        msg = f"inventory snapshot failed: {type(exc).__name__}: {exc}"
+        fetch_error = f"{fetch_error}; {msg}" if fetch_error else msg
+        inventory = load_inventory_snapshot(
+            db_path="/nonexistent-for-fail-soft",
+            lock_dir="/nonexistent-for-fail-soft",
+        )
+
+    remote = getattr(runtime, "remote", None)
+    contamination = _load_contamination_markers(
+        remote=remote,
+        inspect=inspect_contamination,
+        load=load_contamination_payload,
+    )
+    sessions = _build_session_rows(inventory, contamination)
+    return SessionViewSnapshot(
+        runtime=runtime,
+        inventory=inventory,
+        sessions=sessions,
+        contamination_markers=contamination,
+        fetch_error=fetch_error,
+    )
+
+
+def snapshot_to_dict(snapshot: SessionViewSnapshot) -> dict[str, Any]:
+    """JSON export for ``/api/sessions`` (read-only)."""
+    return {
+        "api_version": "v1",
+        "view": "runtime-sessions",
+        "issue": 641,
+        "fetch_error": snapshot.fetch_error,
+        "runtime": runtime_snapshot_to_dict(snapshot.runtime),
+        "inventory": inventory_snapshot_to_dict(snapshot.inventory),
+        "sessions": [row.to_dict() for row in snapshot.sessions],
+        "session_counts": {
+            "total": len(snapshot.sessions),
+            "stale": snapshot.stale_session_count,
+            "contaminated": snapshot.contaminated_session_count,
+        },
+        "contamination_markers": [
+            marker.to_dict() for marker in snapshot.contamination_markers
+        ],
+        "active_contamination": [
+            marker.to_dict() for marker in snapshot.active_contamination
+        ],
+        "recovery_docs": [dict(doc) for doc in snapshot.recovery_docs],
+        "read_only": True,
+        "phase": 1,
+        "mutations": [],
+    }

webui/session_views.py

@@ -0,0 +1,344 @@
+"""HTML views for the Runtime and session view (Phase 1, #641).
+
+Read-only composition of runtime health (#430) and inventory sessions /
+namespaces / worktrees (#636). Surfaces stale and contamination indicators
+when detectable. Recovery links point only at sanctioned reconnect/restart
+docs — never at manual process kill (#630).
+"""
+
+from __future__ import annotations
+
+from html import escape
+from typing import Sequence
+
+from webui.layout import render_page
+from webui.session_loader import (
+    ContaminationMarker,
+    SessionRow,
+    SessionViewSnapshot,
+)
+
+
+def _badge(text: str, css: str) -> str:
+    return f'<span class="badge {css}">{escape(text)}</span>'
+
+
+def _flags(flags: Sequence[str], *, css: str) -> str:
+    if not flags:
+        return '<span class="muted">—</span>'
+    return " ".join(_badge(flag, css) for flag in flags)
+
+
+def _runtime_banner(snapshot: SessionViewSnapshot) -> str:
+    runtime = snapshot.runtime
+    stale = runtime.stale_runtime_warning
+    stale_html = ""
+    if stale:
+        stale_html = (
+            f'<div class="health-card health-stale" style="margin-top:0.75rem;">'
+            f"<strong>Stale runtime:</strong> {escape(stale)}</div>"
+        )
+    identity = runtime.authenticated_username or "unresolved"
+    if runtime.identity_error:
+        identity = f"unresolved ({runtime.identity_error})"
+
+    return f"""<div class="health-card">
+  <h3>Runtime context</h3>
+  <table class="detail">
+    <tr><th>Profile</th><td><code>{escape(runtime.profile_name)}</code></td></tr>
+    <tr><th>Role kind</th><td>{escape(runtime.role_kind)}</td></tr>
+    <tr><th>Identity</th><td>{escape(str(identity))}</td></tr>
+    <tr><th>Remote / host</th>
+      <td><code>{escape(runtime.remote)}</code> · <code>{escape(runtime.host)}</code></td>
+    </tr>
+    <tr><th>Local HEAD</th>
+      <td><code>{escape(runtime.repo_sha or "unknown")}</code></td>
+    </tr>
+    <tr><th>Remote master</th>
+      <td><code>{escape(runtime.remote_master_sha or "unknown")}</code></td>
+    </tr>
+    <tr><th>Commits behind</th>
+      <td>{escape(str(runtime.commits_behind_master if runtime.commits_behind_master is not None else "unknown"))}</td>
+    </tr>
+  </table>
+  <p class="muted">Full runtime detail: <a href="/runtime">/runtime</a> ·
+  Inventory API: <a href="/api/v1/inventory"><code>/api/v1/inventory</code></a></p>
+  {stale_html}
+</div>"""
+
+
+def _summary_bar(snapshot: SessionViewSnapshot) -> str:
+    total = len(snapshot.sessions)
+    stale = snapshot.stale_session_count
+    contaminated = snapshot.contaminated_session_count
+    active_markers = len(snapshot.active_contamination)
+    inv_status = snapshot.inventory.status
+    return f"""<div class="health-card" style="display:flex; flex-wrap:wrap; gap:1rem; align-items:center;">
+  <div><strong>Sessions:</strong> <span class="badge badge-health-ok">{total}</span></div>
+  <div><strong>Stale:</strong> <span class="badge badge-stale">{stale}</span></div>
+  <div><strong>Contaminated:</strong> <span class="badge badge-blocked">{contaminated}</span></div>
+  <div><strong>Active markers:</strong> <span class="badge badge-health-unproven">{active_markers}</span></div>
+  <div><strong>Inventory:</strong> <span class="badge badge-health-skipped">{escape(inv_status)}</span></div>
+</div>"""
+
+
+def _render_session_row(row: SessionRow) -> str:
+    pid = "—" if row.pid is None else str(row.pid)
+    pid_alive = "—" if row.pid_alive is None else ("alive" if row.pid_alive else "dead")
+    pid_css = (
+        "badge-health-ok"
+        if row.pid_alive is True
+        else ("badge-blocked" if row.pid_alive is False else "badge-health-skipped")
+    )
+    leases = (
+        ", ".join(f"<code>{escape(lid)}</code>" for lid in row.lease_ids)
+        if row.lease_ids
+        else '<span class="muted">none</span>'
+    )
+    work = (
+        ", ".join(escape(ref) for ref in row.work_refs)
+        if row.work_refs
+        else '<span class="muted">—</span>'
+    )
+    worktrees = (
+        "<br>".join(f"<code>{escape(path)}</code>" for path in row.worktree_paths)
+        if row.worktree_paths
+        else '<span class="muted">unbound</span>'
+    )
+    return f"""<tr>
+  <td><code>{escape(row.session_id)}</code></td>
+  <td>
+    <div><code>{escape(str(row.role or "—"))}</code> / <code>{escape(str(row.profile or "—"))}</code></div>
+    <div class="muted" style="font-size:0.82rem;">ns: <code>{escape(str(row.namespace or "—"))}</code></div>
+  </td>
+  <td>
+    <code>{escape(pid)}</code>
+    {_badge(pid_alive, pid_css)}
+  </td>
+  <td>{escape(str(row.status or "—"))}<div class="muted" style="font-size:0.82rem;">{escape(str(row.last_heartbeat_at or ""))}</div></td>
+  <td>{leases}<div class="muted" style="font-size:0.82rem; margin-top:0.2rem;">{work}</div></td>
+  <td>{worktrees}</td>
+  <td>{_flags(row.stale_flags, css="badge-stale")}</td>
+  <td>{_flags(row.contamination_flags, css="badge-blocked")}</td>
+</tr>"""
+
+
+def _sessions_table(rows: Sequence[SessionRow]) -> str:
+    if not rows:
+        return (
+            '<p class="muted">No control-plane sessions recorded. Inventory may '
+            "be unavailable, or no MCP workers have registered yet.</p>"
+        )
+    body = "".join(_render_session_row(row) for row in rows)
+    return f"""<table class="registry">
+  <thead>
+    <tr>
+      <th>Session</th>
+      <th>Role / profile / namespace</th>
+      <th>PID</th>
+      <th>Status</th>
+      <th>Leases / work</th>
+      <th>Worktree binding</th>
+      <th>Stale</th>
+      <th>Contamination</th>
+    </tr>
+  </thead>
+  <tbody>
+    {body}
+  </tbody>
+</table>"""
+
+
+def _namespaces_section(snapshot: SessionViewSnapshot) -> str:
+    section = snapshot.inventory.section("namespaces")
+    if section is None:
+        return (
+            '<div class="prompt-card"><h3>Namespaces</h3>'
+            '<p class="muted">Namespaces section not loaded.</p></div>'
+        )
+    if not section.ok:
+        return f"""<div class="prompt-card">
+  <h3>Namespaces {_badge(section.status, "badge-health-degraded")}</h3>
+  <p class="muted">{escape(section.reason or "unavailable")}</p>
+</div>"""
+
+    rows = []
+    for item in section.items:
+        caps = item.get("capability_summary") or {}
+        cap_bits = ", ".join(
+            name for name, ok in sorted(caps.items()) if ok
+        ) or "none"
+        rows.append(
+            "<tr>"
+            f"<td><code>{escape(str(item.get('mcp_namespace') or '—'))}</code></td>"
+            f"<td><code>{escape(str(item.get('profile_name') or '—'))}</code></td>"
+            f"<td>{escape(str(item.get('role') or '—'))}</td>"
+            f"<td>{escape(cap_bits)}</td>"
+            f"<td>{'yes' if item.get('active') else 'no'}</td>"
+            "</tr>"
+        )
+    reason = (
+        f'<p class="muted">{escape(section.reason)}</p>'
+        if section.reason
+        else ""
+    )
+    return f"""<div class="prompt-card">
+  <h3>Namespaces / capabilities</h3>
+  {reason}
+  <table class="registry">
+    <thead>
+      <tr>
+        <th>Namespace</th>
+        <th>Profile</th>
+        <th>Role</th>
+        <th>Capabilities</th>
+        <th>Active in process</th>
+      </tr>
+    </thead>
+    <tbody>
+      {"".join(rows) if rows else '<tr><td colspan="5" class="muted">No namespace rows.</td></tr>'}
+    </tbody>
+  </table>
+</div>"""
+
+
+def _worktrees_section(snapshot: SessionViewSnapshot) -> str:
+    section = snapshot.inventory.section("worktrees")
+    if section is None:
+        return ""
+    if not section.ok and not section.items:
+        return f"""<div class="prompt-card">
+  <h3>Worktrees {_badge(section.status, "badge-health-degraded")}</h3>
+  <p class="muted">{escape(section.reason or "unavailable")}</p>
+</div>"""
+
+    rows = []
+    for item in section.items[:50]:
+        rows.append(
+            "<tr>"
+            f"<td><code>{escape(str(item.get('rel_path') or item.get('path') or '—'))}</code></td>"
+            f"<td><code>{escape(str(item.get('branch') or '—'))}</code></td>"
+            f"<td>{escape(str(item.get('classification') or '—'))}</td>"
+            f"<td>{'yes' if item.get('registered_worktree') else 'no'}</td>"
+            f"<td>{'dirty' if item.get('dirty') else 'clean'}</td>"
+            "</tr>"
+        )
+    more = ""
+    if len(section.items) > 50:
+        more = f'<p class="muted">Showing 50 of {len(section.items)}. Full list: <a href="/worktrees">/worktrees</a>.</p>'
+    return f"""<div class="prompt-card">
+  <h3>Worktree bindings</h3>
+  <p class="muted">Registered issue worktrees under <code>branches/</code>. Hygiene detail: <a href="/worktrees">/worktrees</a>.</p>
+  <table class="registry">
+    <thead>
+      <tr>
+        <th>Path</th>
+        <th>Branch</th>
+        <th>Classification</th>
+        <th>Registered</th>
+        <th>State</th>
+      </tr>
+    </thead>
+    <tbody>
+      {"".join(rows) if rows else '<tr><td colspan="5" class="muted">No worktrees recorded.</td></tr>'}
+    </tbody>
+  </table>
+  {more}
+</div>"""
+
+
+def _contamination_section(markers: Sequence[ContaminationMarker]) -> str:
+    if not markers:
+        return (
+            '<div class="prompt-card"><h3>Contamination markers</h3>'
+            '<p class="muted">No contamination kinds inspected.</p></div>'
+        )
+    rows = []
+    for marker in markers:
+        active = marker.to_dict()["active"]
+        status = "ACTIVE" if active else ("cleared" if marker.cleared else "absent")
+        css = "badge-blocked" if active else "badge-health-ok"
+        rows.append(
+            "<tr>"
+            f"<td><code>{escape(marker.kind)}</code></td>"
+            f"<td>{_badge(status, css)}</td>"
+            f"<td>{escape(marker.reason_class or '—')}</td>"
+            f"<td><code>{escape(marker.session_id or '—')}</code></td>"
+            f"<td>{escape(marker.command_summary or marker.summary)}</td>"
+            "</tr>"
+        )
+    return f"""<div class="prompt-card">
+  <h3>Contamination markers (#630 / #671)</h3>
+  <p class="muted">Durable markers only — never silent when present. Clearance is reconciler-only.</p>
+  <table class="registry">
+    <thead>
+      <tr>
+        <th>Kind</th>
+        <th>State</th>
+        <th>Reason class</th>
+        <th>Session</th>
+        <th>Summary</th>
+      </tr>
+    </thead>
+    <tbody>
+      {"".join(rows)}
+    </tbody>
+  </table>
+</div>"""
+
+
+def _recovery_section(snapshot: SessionViewSnapshot) -> str:
+    items = []
+    for doc in snapshot.recovery_docs:
+        items.append(
+            "<li>"
+            f"<code>{escape(doc['path'])}</code> — "
+            f"<strong>{escape(doc['label'])}</strong>: {escape(doc['note'])}"
+            "</li>"
+        )
+    return f"""<div class="prompt-card">
+  <h3>Sanctioned recovery (read-only)</h3>
+  <p class="muted">This view does <strong>not</strong> restart, kill, or take over sessions.
+  Manual <code>pkill</code> / <code>kill</code> of MCP daemons is contamination (#630), not recovery.</p>
+  <ul class="reasons">
+    {"".join(items)}
+    <li>Prefer IDE/client reconnect (<code>/mcp reconnect</code>) or an operator-owned restart recorded in the restart inventory.</li>
+  </ul>
+</div>"""
+
+
+def render_sessions_page(snapshot: SessionViewSnapshot) -> str:
+    """Render the full HTML body for the runtime/session view."""
+    error_block = ""
+    if snapshot.fetch_error:
+        error_block = (
+            f'<div class="health-card health-stale"><strong>Partial load:</strong> '
+            f"{escape(snapshot.fetch_error)}</div>"
+        )
+    if snapshot.runtime.fetch_error:
+        error_block += (
+            f'<div class="health-card health-stale"><strong>Runtime note:</strong> '
+            f"{escape(snapshot.runtime.fetch_error)}</div>"
+        )
+
+    body = f"""
+{error_block}
+{_runtime_banner(snapshot)}
+{_summary_bar(snapshot)}
+
+<div class="prompt-card">
+  <h3>Sessions</h3>
+  <p class="muted">Control-plane sessions correlated with leases and worktree bindings.
+  Stale and contamination flags are fail-soft: absence of a marker is not proof of cleanliness when inventory is degraded.</p>
+  {_sessions_table(snapshot.sessions)}
+</div>
+
+{_namespaces_section(snapshot)}
+{_worktrees_section(snapshot)}
+{_contamination_section(snapshot.contamination_markers)}
+{_recovery_section(snapshot)}
+"""
+    return render_page(title="Sessions", body_html=f"""<h2>Runtime and sessions</h2>
+<p class="meta">Phase 1 read-only view (#641). Combines runtime health (#430) with
+unified inventory sessions/namespaces/worktrees (#636). No restart or session-takeover controls.</p>
+{body}""")

webui/system_health_views.py

@@ -278,8 +278,10 @@ def _recovery_card() -> str:
         "controls arrive in Phase 2 (#642); until then recovery runs through "
         "the sanctioned client reconnect / operator restart path.</p>"
         "<ul class='reasons'>"
-        "<li><a href='/runtime'>Runtime and session view</a> — active profile, "
+        "<li><a href='/runtime'>Runtime health</a> — active profile, workflow "
-        "workflow hashes, and shell health.</li>"
+        "hashes, and shell health.</li>"
+        "<li><a href='/sessions'>Runtime and sessions</a> — namespaces, session "
+        "rows, worktree bindings, and contamination markers (#641).</li>"
         "<li>Reconnect the MCP client from the IDE, then re-run the blocked "
         "cycle. Never kill the daemon process manually: unmanaged kills are "
         "recorded as runtime contamination (#630).</li>"