fix(webui): authority-aware ownership + redacted contamination text (#641)

Addresses the two blockers from the PR #898 review at a81db754.

B1 - degraded ownership inventory was rendered as affirmative absence.
_build_session_rows read the sessions/leases/locks sections without
consulting their status, so a session row emitted lease_ids=() and
worktree_paths=() whether the session genuinely held nothing or the
lease store simply could not be read. The renderer printed both as
"none" and "unbound", contradicting the ownership_authority_complete
invariant documented on InventorySnapshot.

SessionRow now carries lease_authority and worktree_authority. A
worktree binding is correlated through lease work numbers, so it is
unproven when either the leases or the locks section fails to read --
this covers the narrow variant where locks hold real worktree paths but
a degraded leases section leaves work_numbers empty. The renderer emits
"unknown (inventory <status>)" with an authority-unproven badge instead
of none/unbound, the card names the unreadable sections, and an empty
session list from an unreadable sessions section no longer reads as
"no sessions recorded". snapshot_to_dict exports
ownership_authority_complete, ownership_section_status, and per-row
lease_authority / worktree_authority so /api/sessions consumers can
distinguish the two cases.

B2 - contamination payload strings bypassed redaction.
_inspect_contamination copied command_summary, session_id, role and
reason_class out of the marker payload with only str(), while every
inventory-sourced field on the same page arrives through
webui.inventory.scrub(). The write-time redactor
stable_branch_push_guard.redact_command is a narrow denylist that leaves
absolute $HOME paths, -H 'X-Api-Key: <value>', --password <value>, and
PRIVATE_KEY=<value> intact, and this is the first web surface to render
command_summary at all.

Adds webui.inventory.scrub_text(), which collapses $HOME and redacts
credential-shaped tokens and URL userinfo anywhere inside a string rather
than only at its start, and routes the marker payload through it. scrub()
and every existing caller are untouched. The command_summary field is
kept: it is the #630 evidence naming which daemon was killed. The module
docstring claiming absolute paths were already collapsed is corrected.

Also: removes the locks_by_session_hint dead loop and its discard (N1),
adds the missing trailing newline to webui/runtime_views.py (N4), drops
an unused dataclasses.field import, and documents both honesty rules in
docs/webui-local-dev.md.

Tests: tests/test_webui_sessions_view.py grows from 12 to 26 cases,
covering degraded and unavailable ownership sections in both the HTML and
JSON paths, the locks-readable/leases-degraded variant, a guard against
over-correcting clean inventory into "unknown", the previously untested
expired-lease flag, HTML escaping of hostile values in clean and degraded
renders, and each secret class the write-time denylist misses. The
STATUS_UNAVAILABLE import that was present but unused is now exercised.

Validation, from the issue worktree with venv/bin/python (Python 3.14.5,
pytest 9.1.1):

  pytest tests/test_webui_sessions_view.py tests/test_webui_*.py -q
    -> 512 passed, 376 subtests (was 498 / 372; +14 new tests)
  pytest tests/test_issue_854_semantic_container_exclusion.py -q
    -> 13 passed, 8 subtests
  13-file runtime/health/inventory/restart set
    -> 1 failed, 223 passed; the single failure is
       test_runtime_clarity.py::TestRuntimeClarity::
       test_activate_profile_succeeds_when_enabled, the identical test and
       assertion the reviewer recorded on master at 7af40fb5, so it is
       baseline-equivalent and not introduced here.

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

docs/webui-local-dev.md

@@ -307,6 +307,26 @@ reconnect/operator restart docs (`docs/mcp-namespace-eof-recovery.md`,
 document). The page does **not** restart, kill, or take over sessions; manual
 `pkill` of MCP daemons is contamination, not recovery.
 
+Honesty rules specific to this view:
+
+* **Ownership columns never assert absence they cannot prove.** When the
+  `leases` or `locks` section is degraded or unavailable, the Leases and
+  Worktree-binding cells render `unknown (inventory <status>)` with an
+  *authority unproven* badge instead of `none` / `unbound`, and a caveat names
+  the unreadable sections. A worktree binding is correlated through lease work
+  numbers, so it is unproven when *either* section fails to read.
+  `/api/sessions` carries the same facts as `ownership_authority_complete`,
+  `ownership_section_status`, and per-row `lease_authority` /
+  `worktree_authority`, so a JSON consumer can tell "holds none" from "could
+  not be read".
+* **Contamination text is redacted at the display boundary.** Marker payloads
+  (`command_summary`, `reason_class`, `session_id`, `role`) are
+  operator-supplied free text that does not arrive through inventory scrubbing,
+  so they pass through `webui.inventory.scrub_text`, which collapses `$HOME` and
+  redacts credential-shaped tokens and URL userinfo *anywhere* in the string.
+  The write-time redactor is a narrow denylist and is not relied on. The field
+  itself is kept — it is the `#630` evidence naming which daemon was killed.
+
 ## System-health dashboard (#639)
 
 `/system-health` renders the same snapshot the `/api/v1/system/health` API

tests/test_webui_sessions_view.py

@@ -3,10 +3,16 @@
 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.
+
+Also pins the two invariants a reviewer found violated at head a81db754:
+degraded ownership sections must render as *unknown* rather than as an
+affirmative "none"/"unbound", and contamination payload text must be redacted
+at the display boundary rather than trusted from the write-time denylist.
 """
 
 from __future__ import annotations
 
+import os
 import sys
 import unittest
 from pathlib import Path
@@ -22,6 +28,7 @@ from webui.inventory import (
     AUTHORITY_FILESYSTEM,
     InventorySection,
     InventorySnapshot,
+    STATUS_DEGRADED,
     STATUS_OK,
     STATUS_UNAVAILABLE,
 )
@@ -32,6 +39,7 @@ from webui.session_loader import (
     SessionRow,
     SessionViewSnapshot,
     _build_session_rows,
+    _inspect_contamination,
     load_session_view_snapshot,
     snapshot_to_dict,
 )
@@ -77,36 +85,43 @@ def _inventory(
     locks: tuple[dict, ...] = (),
     worktrees: tuple[dict, ...] = (),
     namespaces: tuple[dict, ...] = (),
+    statuses: dict[str, str] | None = None,
 ) -> InventorySnapshot:
+    """Build a snapshot; ``statuses`` degrades named sections (default all ok)."""
+    status_of = statuses or {}
+
+    def _status(name: str) -> str:
+        return status_of.get(name, STATUS_OK)
+
     sections = (
         InventorySection(
             name="sessions",
             authority=AUTHORITY_CONTROL_PLANE_DB,
-            status=STATUS_OK,
+            status=_status("sessions"),
             items=sessions,
         ),
         InventorySection(
             name="leases",
             authority=AUTHORITY_CONTROL_PLANE_DB,
-            status=STATUS_OK,
+            status=_status("leases"),
             items=leases,
         ),
         InventorySection(
             name="locks",
             authority=AUTHORITY_FILESYSTEM,
-            status=STATUS_OK,
+            status=_status("locks"),
             items=locks,
         ),
         InventorySection(
             name="worktrees",
             authority=AUTHORITY_FILESYSTEM,
-            status=STATUS_OK,
+            status=_status("worktrees"),
             items=worktrees,
         ),
         InventorySection(
             name="namespaces",
             authority=AUTHORITY_FILESYSTEM,
-            status=STATUS_OK,
+            status=_status("namespaces"),
             items=namespaces
             or (
                 {
@@ -453,5 +468,272 @@ class TestSessionsRoutes(unittest.TestCase):
         )
 
 
+class TestDegradedOwnershipAuthority(unittest.TestCase):
+    """B1: a section that could not be read must never render as absence."""
+
+    def _snapshot(self, inventory: InventorySnapshot) -> SessionViewSnapshot:
+        return SessionViewSnapshot(
+            runtime=_runtime(),
+            inventory=inventory,
+            sessions=_build_session_rows(inventory, contamination=()),
+            contamination_markers=(),
+        )
+
+    def test_unavailable_leases_mark_row_authority_unproven(self):
+        inventory = _inventory(
+            sessions=(_clean_session(),),
+            statuses={"leases": STATUS_UNAVAILABLE},
+        )
+        row = _build_session_rows(inventory, contamination=())[0]
+        self.assertEqual(row.lease_ids, ())
+        self.assertEqual(row.lease_authority, STATUS_UNAVAILABLE)
+        # Worktree binding is correlated through lease work numbers, so it
+        # inherits the unreadable lease section.
+        self.assertEqual(row.worktree_authority, STATUS_UNAVAILABLE)
+        self.assertFalse(row.ownership_authority_complete)
+
+    def test_readable_locks_are_not_reported_unbound_when_leases_degrade(self):
+        # The narrow variant: locks hold a real worktree_path and read cleanly,
+        # but the lease section that supplies the correlating work number does
+        # not. The row must say unknown, not "unbound".
+        inventory = _inventory(
+            sessions=(_clean_session(),),
+            locks=(
+                {
+                    "issue_number": 641,
+                    "worktree_path": "branches/feat-issue-641",
+                },
+            ),
+            statuses={"leases": STATUS_DEGRADED},
+        )
+        row = _build_session_rows(inventory, contamination=())[0]
+        self.assertEqual(row.worktree_paths, ())
+        self.assertEqual(row.worktree_authority, STATUS_DEGRADED)
+        self.assertFalse(row.ownership_authority_complete)
+
+    def test_degraded_render_says_unknown_not_none_or_unbound(self):
+        inventory = _inventory(
+            sessions=(_clean_session(),),
+            statuses={"leases": STATUS_UNAVAILABLE, "locks": STATUS_UNAVAILABLE},
+        )
+        html = render_sessions_page(self._snapshot(inventory))
+        self.assertIn("unknown (inventory unavailable)", html)
+        self.assertIn("authority unproven", html)
+        self.assertIn("Ownership authority incomplete", html)
+        # The affirmative-absence strings must be gone from the row entirely.
+        self.assertNotIn(">none<", html)
+        self.assertNotIn(">unbound<", html)
+
+    def test_clean_inventory_still_renders_affirmative_absence(self):
+        # Guards against over-correcting B1 into "everything is unknown".
+        inventory = _inventory(sessions=(_clean_session(),))
+        html = render_sessions_page(self._snapshot(inventory))
+        self.assertIn(">none<", html)
+        self.assertIn(">unbound<", html)
+        # The column legend mentions "unknown (inventory …)" as static copy, so
+        # assert on the per-row marker and the concrete statuses instead.
+        self.assertNotIn("authority unproven", html)
+        self.assertNotIn("unknown (inventory unavailable)", html)
+        self.assertNotIn("unknown (inventory degraded)", html)
+        self.assertNotIn("Ownership authority incomplete", html)
+
+    def test_json_export_carries_snapshot_and_per_row_authority(self):
+        inventory = _inventory(
+            sessions=(_clean_session(),),
+            statuses={"locks": STATUS_UNAVAILABLE},
+        )
+        data = snapshot_to_dict(self._snapshot(inventory))
+        self.assertFalse(data["ownership_authority_complete"])
+        self.assertEqual(
+            data["ownership_section_status"]["locks"], STATUS_UNAVAILABLE
+        )
+        self.assertEqual(data["ownership_section_status"]["leases"], STATUS_OK)
+        self.assertIn("unknown, not unowned", data["ownership_note"])
+
+        row = data["sessions"][0]
+        self.assertTrue(row["lease_authority_complete"])
+        self.assertFalse(row["worktree_authority_complete"])
+        self.assertEqual(row["worktree_authority"], STATUS_UNAVAILABLE)
+        self.assertFalse(row["ownership_authority_complete"])
+        self.assertIn("unknown, not unowned", row["ownership_note"])
+
+    def test_json_export_is_affirmative_when_every_source_reads(self):
+        inventory = _inventory(sessions=(_clean_session(),))
+        data = snapshot_to_dict(self._snapshot(inventory))
+        self.assertTrue(data["ownership_authority_complete"])
+        self.assertTrue(data["sessions"][0]["ownership_authority_complete"])
+
+    def test_missing_session_list_is_not_reported_as_no_sessions(self):
+        inventory = _inventory(statuses={"sessions": STATUS_UNAVAILABLE})
+        html = render_sessions_page(self._snapshot(inventory))
+        self.assertIn("could not be read", html)
+        self.assertIn("not evidence that no sessions exist", html)
+
+    def test_expired_lease_flags_row_as_stale(self):
+        inventory = _inventory(
+            sessions=(_clean_session(),),
+            leases=(
+                {
+                    "lease_id": "lease-expired-1",
+                    "session_id": "prgs-author-111-clean",
+                    "status": "active",
+                    "expired": True,
+                    "work_kind": "issue",
+                    "work_number": 641,
+                },
+            ),
+        )
+        row = _build_session_rows(inventory, contamination=())[0]
+        self.assertIn("lease-expired", row.stale_flags)
+        self.assertIn("active-lease-past-expiry", row.stale_flags)
+
+
+class TestContaminationRedaction(unittest.TestCase):
+    """B2: marker payload text is redacted at the display boundary."""
+
+    def _marker(self, payload: dict) -> ContaminationMarker:
+        return _inspect_contamination(
+            "runtime_recovery_contamination",
+            remote="prgs",
+            inspect=lambda **_k: {
+                "on_disk": True,
+                "has_payload": True,
+                "summary": "",
+            },
+            load=lambda **_k: payload,
+        )
+
+    def test_home_paths_are_collapsed(self):
+        home = os.path.expanduser("~")
+        marker = self._marker(
+            {"command_summary": f"pkill -f {home}/Development/Gitea-Tools/x.py"}
+        )
+        self.assertNotIn(home, marker.command_summary)
+        self.assertIn("~/Development/Gitea-Tools/x.py", marker.command_summary)
+
+    def test_secrets_missed_by_the_write_time_denylist_are_redacted(self):
+        # Each of these was verified in review to survive
+        # stable_branch_push_guard.redact_command untouched.
+        cases = (
+            ("curl -H 'X-Api-Key: SUPERSECRET123' https://example.invalid", "SUPERSECRET123"),
+            ("cmd --password hunter2 origin master", "hunter2"),
+            ("PRIVATE_KEY=abc123 python deploy.py", "abc123"),
+            ("fetch https://user:[email protected]/x.git", "user:pw"),
+        )
+        for raw, secret in cases:
+            with self.subTest(raw=raw):
+                marker = self._marker({"command_summary": raw})
+                self.assertNotIn(secret, marker.command_summary)
+                self.assertIn("[redacted]", marker.command_summary)
+
+    def test_command_summary_is_redacted_not_removed(self):
+        # It is legitimate #630 evidence: the operator must still see which
+        # daemon was killed.
+        marker = self._marker(
+            {
+                "command_summary": "pkill -f gitea_mcp_server.py",
+                "reason_class": "manual_daemon_kill",
+                "session_id": "prgs-author-111-clean",
+                "role": "author",
+            }
+        )
+        self.assertIn("pkill -f gitea_mcp_server.py", marker.command_summary)
+        self.assertEqual(marker.reason_class, "manual_daemon_kill")
+        self.assertEqual(marker.session_id, "prgs-author-111-clean")
+        self.assertEqual(marker.role, "author")
+
+    def test_rendered_page_exposes_no_home_path_from_a_marker(self):
+        home = os.path.expanduser("~")
+        marker = self._marker(
+            {
+                "command_summary": f"pkill -f {home}/Development/Gitea-Tools/x.py",
+                "reason_class": "manual_daemon_kill",
+            }
+        )
+        inventory = _inventory(sessions=(_clean_session(),))
+        html = render_sessions_page(
+            SessionViewSnapshot(
+                runtime=_runtime(),
+                inventory=inventory,
+                sessions=_build_session_rows(inventory, (marker,)),
+                contamination_markers=(marker,),
+            )
+        )
+        self.assertIn("Contamination markers", html)
+        self.assertNotIn(home, html)
+
+
+class TestSessionsPageEscaping(unittest.TestCase):
+    """Hostile values from every rendered source stay inert (N2)."""
+
+    HOSTILE = '<script>alert("xss")</script>'
+
+    def test_hostile_session_and_marker_values_are_escaped(self):
+        session = dict(_clean_session())
+        session["session_id"] = f"sid-{self.HOSTILE}"
+        session["role"] = self.HOSTILE
+        session["profile"] = self.HOSTILE
+        session["namespace"] = self.HOSTILE
+        session["status"] = self.HOSTILE
+        inventory = _inventory(
+            sessions=(session,),
+            leases=(
+                {
+                    "lease_id": self.HOSTILE,
+                    "session_id": session["session_id"],
+                    "status": "active",
+                    "expired": False,
+                    "work_kind": self.HOSTILE,
+                    "work_number": 641,
+                },
+            ),
+            locks=(
+                {
+                    "issue_number": 641,
+                    "worktree_path": self.HOSTILE,
+                },
+            ),
+        )
+        marker = ContaminationMarker(
+            kind="runtime_recovery_contamination",
+            on_disk=True,
+            has_payload=True,
+            summary=self.HOSTILE,
+            reason_class=self.HOSTILE,
+            session_id=session["session_id"],
+            role=self.HOSTILE,
+            command_summary=self.HOSTILE,
+            cleared=False,
+        )
+        html = render_sessions_page(
+            SessionViewSnapshot(
+                runtime=_runtime(),
+                inventory=inventory,
+                sessions=_build_session_rows(inventory, (marker,)),
+                contamination_markers=(marker,),
+            )
+        )
+        self.assertNotIn("<script>", html)
+        self.assertNotIn('alert("xss")', html)
+        self.assertIn("&lt;script&gt;", html)
+
+    def test_hostile_values_in_a_degraded_render_are_escaped(self):
+        inventory = _inventory(
+            sessions=(dict(_clean_session(), session_id=f"sid-{self.HOSTILE}"),),
+            statuses={"leases": STATUS_UNAVAILABLE, "locks": STATUS_DEGRADED},
+        )
+        html = render_sessions_page(
+            SessionViewSnapshot(
+                runtime=_runtime(),
+                inventory=inventory,
+                sessions=_build_session_rows(inventory, contamination=()),
+                contamination_markers=(),
+            )
+        )
+        self.assertNotIn("<script>", html)
+        self.assertIn("&lt;script&gt;", html)
+        self.assertIn("unknown (inventory", html)
+
+
 if __name__ == "__main__":
     unittest.main()

webui/inventory.py

@@ -76,6 +76,35 @@ _CREDENTIAL_KEY_RE = re.compile(
 )
 _REDACTED = "[redacted]"
 
+#: Credential-shaped *name* as it appears inside a free-form command line. This
+#: is deliberately broader than :data:`_CREDENTIAL_KEY_RE` — it also matches a
+#: bare ``key`` component, so ``PRIVATE_KEY=`` is caught. Over-redacting a
+#: displayed string is safe; under-redacting one is not.
+_TEXT_CREDENTIAL_NAME = (
+    r"[A-Za-z0-9_.\-]*"
+    r"(?:token|secret|password|passwd|key|authorization|bearer|credential)"
+    r"[A-Za-z0-9_.\-]*"
+)
+#: A value following such a name: single-quoted, double-quoted, or bare. The
+#: bare form stops at a quote so an enclosing quote survives the redaction.
+_TEXT_CREDENTIAL_VALUE = r"'[^']*'|\"[^\"]*\"|[^\s'\"]+"
+
+_TEXT_CREDENTIAL_FLAG_RE = re.compile(
+    rf"(?P<key>(?<![\w\-])--?{_TEXT_CREDENTIAL_NAME})"
+    rf"(?P<sep>[=\s]+)"
+    rf"(?P<value>{_TEXT_CREDENTIAL_VALUE})",
+    re.IGNORECASE,
+)
+_TEXT_CREDENTIAL_ASSIGN_RE = re.compile(
+    rf"(?P<key>(?<![\w\-]){_TEXT_CREDENTIAL_NAME})"
+    rf"(?P<sep>\s*[:=]\s*)"
+    rf"(?P<value>{_TEXT_CREDENTIAL_VALUE})",
+    re.IGNORECASE,
+)
+_TEXT_URL_USERINFO_RE = re.compile(
+    r"(?P<scheme>\b[A-Za-z][A-Za-z0-9+.\-]*://)[^\s/@]+@"
+)
+
 
 @dataclass(frozen=True)
 class InventorySection:
@@ -225,6 +254,42 @@ def scrub(value: Any, *, key: str | None = None) -> Any:
     return repr(value)
 
 
+def collapse_home(text: str) -> str:
+    """Collapse every ``$HOME`` occurrence *inside* a string, not just a prefix."""
+    home = os.path.expanduser("~")
+    if not home or home == "/":
+        return text
+    return text.replace(home, "~")
+
+
+def scrub_text(value: Any) -> Any:
+    """Redact a free-form text blob such as a recorded command line.
+
+    :func:`scrub` keys off structured field *names* and whole-value prefixes,
+    which is right for inventory records but blind to a secret embedded in the
+    middle of a sentence. This collapses ``$HOME`` and redacts credential-shaped
+    tokens and URL userinfo *anywhere* in the string, so operator-supplied text
+    rendered verbatim — contamination ``command_summary`` (#630) above all — is
+    held to the same standard as every other field on the page.
+
+    Returns ``None`` unchanged so callers can keep "absent" distinct from "".
+    """
+    if value is None:
+        return None
+    text = value if isinstance(value, str) else str(value)
+    text = collapse_home(text)
+    text = _TEXT_URL_USERINFO_RE.sub(
+        lambda m: f"{m.group('scheme')}{_REDACTED}@", text
+    )
+    text = _TEXT_CREDENTIAL_FLAG_RE.sub(
+        lambda m: f"{m.group('key')}{m.group('sep')}{_REDACTED}", text
+    )
+    text = _TEXT_CREDENTIAL_ASSIGN_RE.sub(
+        lambda m: f"{m.group('key')}{m.group('sep')}{_REDACTED}", text
+    )
+    return text
+
+
 # ── control-plane database (read-only) ───────────────────────────────────────
 
 

webui/runtime_views.py

@@ -91,4 +91,4 @@ def render_runtime_page(snapshot: RuntimeSnapshot) -> str:
         "<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/session_loader.py

@@ -12,18 +12,30 @@ Sources:
   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.
+Secrets are never read. Inventory-sourced values arrive already redacted by
+:func:`webui.inventory.scrub`; free-form marker text this module loads itself is
+put through :func:`webui.inventory.scrub_text`, which collapses ``$HOME`` and
+redacts credential-shaped tokens *inside* a string rather than only at its start.
+
+Ownership columns are authority-aware. A lease or lock section that could not be
+read renders as ``unknown``, never as ``none`` or ``unbound``: a lease the reader
+could not load is not an absent lease (see
+:attr:`webui.inventory.InventorySnapshot.ownership_authority_complete`).
 """
 
 from __future__ import annotations
 
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from typing import Any, Callable
 
 import mcp_session_state
 from webui.inventory import (
+    OWNERSHIP_SECTIONS,
+    STATUS_OK,
+    InventorySection,
     InventorySnapshot,
     load_inventory_snapshot,
+    scrub_text,
     snapshot_to_dict as inventory_snapshot_to_dict,
 )
 from webui.runtime_health import (
@@ -61,6 +73,29 @@ _CONTAMINATION_KINDS: tuple[str, ...] = (
     mcp_session_state.KIND_STABLE_BRANCH_CONTAMINATION,
 )
 
+#: Status recorded on a row when the backing inventory section is absent
+#: entirely — distinct from a section that reported itself degraded.
+AUTHORITY_MISSING = "missing"
+
+
+def _section_status(section: InventorySection | None) -> str:
+    """Status of an ownership section, treating an absent section as missing."""
+    if section is None:
+        return AUTHORITY_MISSING
+    return section.status
+
+
+def _combined_authority(*statuses: str) -> str:
+    """Worst status of the sections a derived column depends on.
+
+    A column proved from two sections is only trustworthy when *both* read
+    cleanly, so the first non-``ok`` status wins.
+    """
+    for status in statuses:
+        if status != STATUS_OK:
+            return status
+    return STATUS_OK
+
 
 @dataclass(frozen=True)
 class ContaminationMarker:
@@ -109,6 +144,17 @@ class SessionRow:
     worktree_paths: tuple[str, ...] = ()
     stale_flags: tuple[str, ...] = ()
     contamination_flags: tuple[str, ...] = ()
+    #: Status of the section backing ``lease_ids``/``work_refs``. While this is
+    #: not ``ok`` those tuples mean "could not be read", never "none held".
+    lease_authority: str = STATUS_OK
+    #: Worst status across the sections backing ``worktree_paths`` (locks are
+    #: correlated through lease work numbers, so both must read cleanly).
+    worktree_authority: str = STATUS_OK
+
+    @property
+    def ownership_authority_complete(self) -> bool:
+        """True only when this row's ownership columns are provable."""
+        return self.lease_authority == STATUS_OK and self.worktree_authority == STATUS_OK
 
     def to_dict(self) -> dict[str, Any]:
         return {
@@ -128,6 +174,18 @@ class SessionRow:
             "contamination_flags": list(self.contamination_flags),
             "is_stale": bool(self.stale_flags),
             "is_contaminated": bool(self.contamination_flags),
+            "lease_authority": self.lease_authority,
+            "worktree_authority": self.worktree_authority,
+            "lease_authority_complete": self.lease_authority == STATUS_OK,
+            "worktree_authority_complete": self.worktree_authority == STATUS_OK,
+            "ownership_authority_complete": self.ownership_authority_complete,
+            "ownership_note": (
+                "Lease and worktree columns are proved from sections that read "
+                "cleanly."
+                if self.ownership_authority_complete
+                else "An ownership source could not be read; empty lease_ids or "
+                "worktree_paths on this row mean unknown, not unowned."
+            ),
         }
 
 
@@ -154,6 +212,19 @@ class SessionViewSnapshot:
     def active_contamination(self) -> tuple[ContaminationMarker, ...]:
         return tuple(m for m in self.contamination_markers if m.to_dict()["active"])
 
+    @property
+    def ownership_authority_complete(self) -> bool:
+        """False while any ownership section is degraded, absent, or unavailable."""
+        return self.inventory.ownership_authority_complete
+
+    @property
+    def ownership_section_status(self) -> dict[str, str]:
+        """Per-section status for the three ownership-bearing sections."""
+        return {
+            name: _section_status(self.inventory.section(name))
+            for name in OWNERSHIP_SECTIONS
+        }
+
 
 def _inspect_contamination(
     kind: str,
@@ -180,7 +251,7 @@ def _inspect_contamination(
     role = None
     command_summary = None
     cleared = False
-    summary = str(envelope.get("summary") or "")
+    summary = scrub_text(str(envelope.get("summary") or ""))
 
     if envelope.get("on_disk") and envelope.get("has_payload"):
         try:
@@ -194,20 +265,25 @@ def _inspect_contamination(
             command_summary = payload.get("command_summary") or payload.get("detail")
             cleared = bool(payload.get("cleared_by_reconciler"))
             if not summary:
-                summary = (
+                summary = scrub_text(
                     f"{kind}: {reason_class or 'present'}"
                     + (" (cleared)" if cleared else "")
                 )
 
+    # Marker payloads are operator-supplied free text and are the one thing on
+    # this page that does not arrive through inventory scrubbing. The write-time
+    # redactor is a narrow denylist, so redact again at the display boundary:
+    # it leaves $HOME paths, `-H 'X-Api-Key: …'`, `--password …`, and
+    # `PRIVATE_KEY=…` intact. The field itself stays — it is #630 evidence.
     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,
+        reason_class=scrub_text(str(reason_class)) if reason_class else None,
-        session_id=str(session_id) if session_id else None,
+        session_id=scrub_text(str(session_id)) if session_id else None,
-        role=str(role) if role else None,
+        role=scrub_text(str(role)) if role else None,
-        command_summary=str(command_summary) if command_summary else None,
+        command_summary=scrub_text(str(command_summary)) if command_summary else None,
         cleared=cleared,
     )
 
@@ -232,18 +308,21 @@ def _build_session_rows(
     leases_section = inventory.section("leases")
     locks_section = inventory.section("locks")
 
+    # Ownership columns may only assert absence when their source read cleanly.
+    lease_authority = _section_status(leases_section)
+    # Locks carry claimant profile/username, not control-plane session ids, so a
+    # worktree binding is correlated through lease work numbers: it depends on
+    # the locks *and* the leases section.
+    worktree_authority = _combined_authority(
+        lease_authority, _section_status(locks_section)
+    )
+
     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
@@ -324,11 +403,11 @@ def _build_session_rows(
                 worktree_paths=tuple(worktree_paths),
                 stale_flags=tuple(dict.fromkeys(stale_flags)),
                 contamination_flags=tuple(dict.fromkeys(contamination_flags)),
+                lease_authority=lease_authority,
+                worktree_authority=worktree_authority,
             )
         )
 
-    # Silence unused variable for the locks_by_session_hint placeholder path.
-    _ = locks_by_session_hint
     return tuple(rows)
 
 
@@ -415,6 +494,16 @@ def snapshot_to_dict(snapshot: SessionViewSnapshot) -> dict[str, Any]:
             "stale": snapshot.stale_session_count,
             "contaminated": snapshot.contaminated_session_count,
         },
+        "ownership_authority_complete": snapshot.ownership_authority_complete,
+        "ownership_section_status": snapshot.ownership_section_status,
+        "ownership_note": (
+            "Every ownership source read cleanly; a session with no lease and no "
+            "worktree path genuinely holds neither."
+            if snapshot.ownership_authority_complete
+            else "An ownership source is degraded or unavailable. Empty lease_ids "
+            "and worktree_paths mean unknown, not unowned; consult each row's "
+            "lease_authority and worktree_authority."
+        ),
         "contamination_markers": [
             marker.to_dict() for marker in snapshot.contamination_markers
         ],

webui/session_views.py

@@ -11,6 +11,7 @@ from __future__ import annotations
 from html import escape
 from typing import Sequence
 
+from webui.inventory import STATUS_OK
 from webui.layout import render_page
 from webui.session_loader import (
     ContaminationMarker,
@@ -29,6 +30,19 @@ def _flags(flags: Sequence[str], *, css: str) -> str:
     return " ".join(_badge(flag, css) for flag in flags)
 
 
+def _unproven_cell(status: str) -> str:
+    """Render an ownership column whose backing inventory section failed to read.
+
+    Never "none" and never "unbound": an unreadable source proves nothing about
+    ownership, and claiming otherwise is the exact failure the
+    ``ownership_authority_complete`` invariant exists to prevent.
+    """
+    return (
+        f'<span class="muted">unknown (inventory {escape(status)})</span><br>'
+        f'{_badge("authority unproven", "badge-health-degraded")}'
+    )
+
+
 def _runtime_banner(snapshot: SessionViewSnapshot) -> str:
     runtime = snapshot.runtime
     stale = runtime.stale_runtime_warning
@@ -73,15 +87,37 @@ def _summary_bar(snapshot: SessionViewSnapshot) -> str:
     contaminated = snapshot.contaminated_session_count
     active_markers = len(snapshot.active_contamination)
     inv_status = snapshot.inventory.status
+    authority_complete = snapshot.ownership_authority_complete
+    authority_text = "complete" if authority_complete else "incomplete"
+    authority_css = "badge-health-ok" if authority_complete else "badge-health-degraded"
     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><strong>Ownership authority:</strong> <span class="badge {authority_css}">{authority_text}</span></div>
 </div>"""
 
 
+def _ownership_caveat(snapshot: SessionViewSnapshot) -> str:
+    """Name the unreadable ownership sections, or render nothing when all read."""
+    if snapshot.ownership_authority_complete:
+        return ""
+    degraded = ", ".join(
+        f"{name}: {status}"
+        for name, status in snapshot.ownership_section_status.items()
+        if status != STATUS_OK
+    )
+    return (
+        '<div class="health-card health-stale">'
+        "<strong>Ownership authority incomplete:</strong> "
+        f"{escape(degraded)}. Columns marked <em>unknown</em> could not be read. "
+        "No session below may be treated as holding no lease or no worktree "
+        "binding — absence of evidence is not evidence of absence.</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")
@@ -90,21 +126,33 @@ def _render_session_row(row: SessionRow) -> str:
         if row.pid_alive is True
         else ("badge-blocked" if row.pid_alive is False else "badge-health-skipped")
     )
-    leases = (
+    # An empty tuple only means "holds none" when its source read cleanly.
-        ", ".join(f"<code>{escape(lid)}</code>" for lid in row.lease_ids)
+    if row.lease_authority != STATUS_OK:
-        if row.lease_ids
+        lease_cell = _unproven_cell(row.lease_authority)
-        else '<span class="muted">none</span>'
+    else:
-    )
+        leases = (
-    work = (
+            ", ".join(f"<code>{escape(lid)}</code>" for lid in row.lease_ids)
-        ", ".join(escape(ref) for ref in row.work_refs)
+            if row.lease_ids
-        if row.work_refs
+            else '<span class="muted">none</span>'
-        else '<span class="muted">—</span>'
+        )
-    )
+        work = (
-    worktrees = (
+            ", ".join(escape(ref) for ref in row.work_refs)
-        "<br>".join(f"<code>{escape(path)}</code>" for path in row.worktree_paths)
+            if row.work_refs
-        if row.worktree_paths
+            else '<span class="muted">—</span>'
-        else '<span class="muted">unbound</span>'
+        )
-    )
+        lease_cell = (
+            f'{leases}<div class="muted" style="font-size:0.82rem; '
+            f'margin-top:0.2rem;">{work}</div>'
+        )
+
+    if row.worktree_authority != STATUS_OK:
+        worktrees = _unproven_cell(row.worktree_authority)
+    else:
+        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>
@@ -116,15 +164,24 @@ def _render_session_row(row: SessionRow) -> str:
     {_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>{lease_cell}</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:
+def _sessions_table(snapshot: SessionViewSnapshot) -> str:
+    rows: Sequence[SessionRow] = snapshot.sessions
     if not rows:
+        sessions_status = snapshot.ownership_section_status.get("sessions", STATUS_OK)
+        if sessions_status != STATUS_OK:
+            return (
+                '<p class="muted">Session inventory is '
+                f"<strong>{escape(sessions_status)}</strong> — the session list "
+                "could not be read. This is not evidence that no sessions "
+                "exist.</p>"
+            )
         return (
             '<p class="muted">No control-plane sessions recorded. Inventory may '
             "be unavailable, or no MCP workers have registered yet.</p>"
@@ -329,8 +386,10 @@ def render_sessions_page(snapshot: SessionViewSnapshot) -> str:
 <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>
+  Stale and contamination flags are fail-soft: absence of a marker is not proof of cleanliness when inventory is degraded.
-  {_sessions_table(snapshot.sessions)}
+  Lease and worktree columns read <em>unknown (inventory …)</em> when their source could not be loaded.</p>
+  {_ownership_caveat(snapshot)}
+  {_sessions_table(snapshot)}
 </div>
 
 {_namespaces_section(snapshot)}