fix: head-scope durable #332 review-decision locks (#620)

Prior REQUEST_CHANGES on head A no longer blocks formal re-review on
head B of the same open PR. Locks store reviewed head SHA, hard-stop and
mark_ready/submit gates allow a fresh decision boundary when the live
head differs, and same-head duplicates remain fail-closed. Open-PR lock
cleanup stays forbidden (#594); assessment reports locked vs current
head and stale_by_head / fresh_review_on_current_head_allowed.

Closes #620

docs/architecture/mcp-allocator-control-plane-observability-adr.md

@@ -0,0 +1,301 @@
+# ADR: MCP allocator, control-plane DB, and Sentry/GlitchTip incident bridge architecture
+
+- **Status:** Accepted (implementation pending; blocks code for #600 / #612 / #613)
+- **Date:** 2026-07-09
+- **Tracking issues:**
+  - [#613](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/613) — control-plane DB (first)
+  - [#600](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/600) — allocator API (second)
+  - [#612](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/612) — Sentry/GlitchTip incident bridge (third)
+- **Related:** existing GlitchTip contracts (`glitchtip-to-gitea-workflow-design.md`, `glitchtip-gitea-deduplication-linking-design.md`), trust boundaries (`tool-boundaries.md`, `safety-model.md`), current leases (`pr_work_lease.py`, `issue_lock_store.py`)
+
+## 1. Context
+
+Multiple LLM sessions can independently inspect the Gitea queue and start the same issue or PR. Existing coordination (Gitea comment leases, local issue-lock files, labels) often detects collisions **after** work has started. Parallel issues #600, #612, and #613 each describe part of a fix; without one ADR they risk overlapping stores, wrong dependency order, and trust-boundary violations.
+
+This ADR is the canonical architecture decision **before** implementing those issues.
+
+## 2. Decision summary (core)
+
+| Layer | Owns | Must not |
+|-------|------|----------|
+| **Control-plane DB** | Sessions, atomic assignment, leases, heartbeats, terminal-lock index, events, incident links | Bypass Gitea workflow gates or replace issue/PR history |
+| **Gitea** | Durable work record: issues, PRs, comments, labels, reviews, merges | Be the only concurrency lock under multi-session load |
+| **Sentry / GlitchTip** | Incidents, events, provider UI | Assign work, approve/merge/close, or mutate Gitea outside the bridge |
+| **Incident bridge** | Provider adapters, reconcile/create Gitea issues, link storage upsert, optional provider writeback | Hand raw provider incidents to the allocator as work items |
+
+**One-liner:** **DB coordinates. Gitea records. Sentry/GlitchTip observe. The bridge is the only path that turns observations into Gitea work. The allocator assigns only Gitea issues/PRs, never raw monitoring incidents.**
+
+## 3. Dependency order
+
+Implementation **must** follow:
+
+```text
+#613 control-plane DB  →  #600 allocator API  →  #612 incident bridge
+   (atomic substrate)      (routing policy)       (feeds Gitea work)
+```
+
+| Issue | Role | Depends on |
+|-------|------|------------|
+| **#613** | Durable coordination DB + lease/assignment transactions | — |
+| **#600** | `gitea_allocate_next_work` policy and tool surface | **#613** (hard) |
+| **#612** | Multi-project Sentry/GlitchTip → Gitea bridge | **#613** for `incident_links` index; **#600** before treating bridge-created issues as allocator feed in multi-worker prod |
+
+**Hard rules:**
+
+1. Do **not** implement #600 on file locks / comment-only leases and call it done.
+2. Do **not** ship #612 as a second assignment system for raw incidents.
+3. Partial previews (read-only list tools, schema stubs) may land earlier if they do not claim “allocator complete” or “bridge complete.”
+
+## 4. Authority boundaries
+
+### 4.1 Gitea (durable source of truth for work)
+
+Gitea remains authoritative for:
+
+- Issue and PR identity, titles, bodies, state (open/closed/merged)
+- Comments, reviews, approvals, REQUEST_CHANGES
+- Labels and workflow status labels (`status:ready`, `status:in-progress`, …)
+- Merges, closes, branch refs as recorded by Gitea/git hosting
+
+Operators and auditors read **history** from Gitea.
+
+### 4.2 Control-plane DB (coordination / index)
+
+The control-plane DB is authoritative for **live multi-session coordination**:
+
+- Which session holds which assignment/lease
+- Heartbeat freshness and expiry
+- Terminal-lock index for routing
+- Event log of allocation/lease transitions
+- `incident_links` index (see §8)
+
+It is **not** a substitute for Gitea history. When DB and Gitea disagree on durable work state (e.g. PR already merged), **Gitea wins**; the DB is reconciled.
+
+### 4.3 Sentry / GlitchTip (observe)
+
+Providers own incident lifecycle and raw event data. They:
+
+- Must **not** bypass Gitea gates
+- Must **not** assign LLM work
+- May receive **writeback** of resolution status only through the bridge, when configured and supported
+
+### 4.4 Trust boundaries for credentials
+
+Aligned with `docs/tool-boundaries.md` and `docs/safety-model.md`:
+
+- **One MCP server process per trust boundary** remains the default.
+- Monitor API tokens (Sentry/GlitchTip) live in the **bridge/orchestrator boundary** (or a dedicated observability write/read profile), **not** blindly inside every Gitea MCP author/reviewer/merger process.
+- Gitea tokens stay on Gitea MCP profiles only.
+- Orchestrators compose services; they must not become a single credential pool that silently mixes Gitea write + monitor tokens into every worker.
+
+Tool names such as `gitea_observability_*` may exist as a **namespace façade** only if the runtime still enforces separate credential scopes (e.g. bridge process vs pure Gitea mutation process).
+
+## 5. Allocator rules (#600 on top of #613)
+
+### 5.1 Worker contract
+
+- Workers **do not self-select** work under the standard multi-LLM workflow.
+- Workers call **`gitea_allocate_next_work`** (with `apply=true` only when taking work).
+- Mutations that claim exclusive work require a **valid assignment and lease** from the control-plane DB.
+- Return values include at least: role, issue/PR number, expected head SHA (when applicable), lease ID, expiry, allowed actions, forbidden actions — or a non-assignment outcome (`WAIT`, terminal-path block, no safe work, needs controller, etc.).
+
+### 5.2 Atomic reserve
+
+- **Assignment creation and lease creation happen in one DB transaction.**
+- Two concurrent sessions **must not** receive the same issue/PR as assigned work.
+- On contention: second session gets **WAIT** or **owner-resume**, never a duplicate lease.
+
+### 5.3 Routing policy
+
+| Condition | Route |
+|-----------|--------|
+| Current-head **REQUEST_CHANGES** | **Author** (not reviewer/merger) |
+| **Stale** approval (approval not on current head) | **Reviewer** |
+| **Clean** approval on current head, mergeable | **Merger** |
+| Contested / contaminated approval | **Diagnosis / reconciler** (controller path) |
+| Active **foreign** lease | **WAIT** or **owner-resume** |
+| **Terminal-review** lock present | **Terminal-path resolution first** before downstream review work |
+| Merged / closed PR | **Never assign** |
+| Issue locked by sanctioned lease | **Never assign** to another worker unless lease cleanup/adoption is sanctioned |
+
+### 5.4 Relationship to Gitea mirrors
+
+After a successful assignment, the allocator (or sanctioned tooling) may update Gitea comments/labels so humans and audits see state. Those mirrors **are not** the sole lock source.
+
+## 6. Control-plane DB topology (#613)
+
+### 6.1 Preferred architecture (multi-daemon / Proxmox)
+
+For true multi-session concurrency (multiple MCP daemons, multiple hosts, or Proxmox VMs):
+
+**Prefer either:**
+
+1. **Shared Postgres** used by all Gitea MCP profiles / allocator callers, **or**
+2. A **single allocator daemon** (sole writer to the coordination store) that all workers call over MCP/RPC.
+
+Both satisfy: one transactional authority for “who has this work item.”
+
+### 6.2 SQLite MVP
+
+SQLite is acceptable **only** for a **single-writer MVP**:
+
+- One process owns writes (allocator daemon or single co-located MCP server), **or**
+- Documented single-host single-daemon experiments with file locking and no multi-host claims.
+
+SQLite is **not** sufficient to declare multi-session production readiness when four independent LLM sessions talk to four MCP processes without a shared writer.
+
+### 6.3 Suggested entities (normative shape)
+
+Minimum logical entities (names may vary; semantics must not):
+
+1. **sessions** — session_id, role/profile, namespace, pid, started_at, last_heartbeat_at, status  
+2. **work_items** — remote/org/repo, kind ∈ {`issue`, `pr`}, number, state, priority, current_head_sha, updated_at  
+3. **leases** — lease_id, work_item_id, session_id, role, phase, expires_at, heartbeat_at, status  
+4. **assignments** — assignment_id, work_item_id, session_id, allowed_action(s), expected_head_sha, status  
+5. **terminal_locks** — repo/org, terminal_pr, review_id, decision, status, cleanup_state  
+6. **events** — event_id, work_item_id, type, message, created_at  
+7. **incident_links** — provider-neutral link model (see §8)
+
+**Explicit non-kind:** do **not** use `work_items.kind = sentry_incident` (or glitchtip_incident) as an assignable work unit. Incidents become work only after the bridge creates/links a **Gitea issue**.
+
+## 7. Lease migration (avoid split-brain)
+
+### 7.1 Target state
+
+- **Primary** for live coordination: **control-plane DB** leases and assignments.
+- **Gitea comment leases** (e.g. `<!-- mcp-review-lease:v1 -->`) and **local issue-lock files** become:
+  - **mirrors** of DB state for human visibility / recovery, and/or
+  - written **only** through the allocator (or sanctioned lease tools that update DB + mirror in one workflow).
+
+### 7.2 Migration rules
+
+1. New exclusive claims go through DB assignment+lease first.
+2. Comment lease / file lock writers that skip the DB are **deprecated** once #613+#600 land.
+3. Reconciler tooling heals: expired DB lease, orphan Gitea comment, orphan local file — fail closed when ambiguous.
+4. **Split-brain is a defect:** “DB free + Gitea comment leased” or “DB leased + Gitea free” must be detectable and reconcilable; production paths must not rely on two independent writers.
+
+### 7.3 Heartbeats
+
+- Heartbeats update the **DB**.
+- Optional Gitea summaries must avoid comment spam (periodic summary or edit-in-place policy).
+
+## 8. Observability bridge (#612)
+
+### 8.1 Role
+
+The bridge:
+
+1. Scans configured Sentry and/or GlitchTip projects (multi-project mappings).
+2. Deduplicates against existing links / Gitea issues.
+3. Creates or updates **normal Gitea issues** (labels, sanitized body, provider URL).
+4. Upserts **one** canonical `incident_links` row.
+5. Optionally writes resolution status back to the provider when supported.
+6. Never approves, merges, closes, or otherwise bypasses Gitea workflow gates.
+
+### 8.2 Allocator interaction
+
+- The allocator sees observability work **only after** a Gitea issue exists (typically `status:ready` + observability labels).
+- **Do not assign raw Sentry/GlitchTip incidents** as work items.
+- Bridge AC “allocator can see linked issues” means: **as ordinary Gitea issues**, not a special incident queue.
+
+### 8.3 Provider adapters and trust
+
+- Separate **Sentry** and **GlitchTip** adapters; document API differences; do not assume writeback parity.
+- Self-hosted base URLs supported (e.g. `https://sentry.prgs.cc`).
+- Tokens from environment / secret store only.
+- Prefer phase-1 **explicit reconcile / dry-run** before unsupervised watchdog auto-filing, consistent with existing GlitchTip filing safety contracts.
+
+### 8.4 Home of implementation
+
+Filing/orchestration may live in:
+
+- a control-plane / bridge package or profile, and/or  
+- Gitea-Tools as operator-facing tools that **delegate** to that boundary,
+
+but must not violate §4.4 credential isolation.
+
+## 9. Incident link storage (single source of truth)
+
+### 9.1 Canonical model: `incident_links` (provider-neutral)
+
+Prefer a **provider-neutral** model over Sentry-only `sentry_links`:
+
+| Field (logical) | Purpose |
+|-----------------|---------|
+| provider | `sentry` \| `glitchtip` \| … |
+| provider_base_url | Self-hosted base |
+| provider_org / provider_project | Mapping key |
+| provider_issue_id / provider_short_id | Provider identity |
+| provider_permalink | Human URL |
+| fingerprint | Stable dedupe key when available |
+| gitea_org / gitea_repo / gitea_issue_number | Linked work |
+| linked_pr_numbers | Optional PR association |
+| first_seen / last_seen / event_count | Summary metrics (safe) |
+| status | link lifecycle |
+| release_resolved_at / last_sync_at | Sync bookkeeping |
+
+### 9.2 Gitea as human mirror
+
+- Issue body markers / structured comments (e.g. HTML comment metadata) remain the **human- and audit-visible mirror**.
+- They must stay consistent with `incident_links` but are **not** a second independent write path for inventing links without the bridge.
+
+### 9.3 One truth
+
+- **Do not** maintain two independent systems of record (e.g. full mapping only in #612 storage **and** a separate #613 `sentry_links` with different semantics).
+- #612 implementation **must** use the same `incident_links` model introduced under #613 (or a single agreed store both reference).
+
+## 10. Security and redaction
+
+Mandatory for bridge payloads, Gitea issue bodies/comments, DB-stored event summaries, and logs:
+
+- No API tokens, DSNs, passwords, cookies, auth headers
+- No keychain IDs, private config contents, raw session-state files, full prompt bodies
+- Sanitize stack locals and request data; store only safe tags/context
+- Logs must never print provider tokens or DSNs
+- Redaction tests are required for #612
+
+## 11. Non-goals
+
+- Replace Gitea as the durable workflow record  
+- Let Sentry/GlitchTip assign work or mutate Gitea workflow state outside sanctioned tools  
+- Let the bridge approve, merge, close, release, or bypass Gitea gates  
+- Implement #600 on file locks / comments alone and call allocator complete  
+- Treat raw monitoring incidents as `work_items` for the allocator  
+- Put monitor tokens into every Gitea MCP worker process by default  
+
+## 12. Consequences
+
+### Positive
+
+- Clear implementation order and ownership  
+- Multi-session safety becomes testable at the DB layer  
+- Observability becomes assignable work without special-casing the allocator  
+- Trust boundaries stay compatible with existing control-plane docs  
+
+### Costs / risks
+
+- Migration from comment/file leases requires reconciler work  
+- Shared Postgres or single allocator daemon is operational cost  
+- Bridge must be careful not to spam Gitea issues (dedupe, caps, policy modes)  
+
+### Follow-ups (documentation only until implemented)
+
+1. Update #600, #612, and #613 bodies to **link this ADR** and restate hard dependencies.  
+2. Implement #613 schema + atomic assign/lease.  
+3. Implement #600 against the DB.  
+4. Implement #612 against `incident_links` + Gitea create/update.  
+5. Deprecate dual writers for leases.
+
+## 13. Acceptance criteria for *this* ADR
+
+This document is accepted when:
+
+1. It is merged into `docs/architecture/` on the default branch.  
+2. #600 / #612 / #613 (or their PRs) reference this path as the architecture source of truth.  
+3. No implementation PR for those issues claims completion without conforming to §§2–11.
+
+## 14. Document history
+
+| Date | Change |
+|------|--------|
+| 2026-07-09 | Initial ADR: dependency order, authority model, topology, lease migration, bridge, `incident_links`, security, non-goals |

docs/mcp-namespace-eof-recovery.md

@@ -0,0 +1,118 @@
+# Recovering from `client is closing: EOF` on a Gitea MCP namespace (#543)
+
+## Symptom
+
+A tool call through a Gitea MCP namespace — `gitea-author`, `gitea-reviewer`,
+`gitea-merger`, or the shared `gitea-tools` namespace — fails immediately with:
+
+```
+client is closing: EOF
+```
+
+Every subsequent call to that same namespace returns the same error, including
+cheap read tools such as `gitea_whoami` and `gitea_list_profiles`. Other MCP
+servers registered with the same client (for example `context7`) keep working,
+so this is **not** a global MCP-client outage.
+
+## Why this is not a code defect
+
+This failure is a **transport-level** condition in the IDE / MCP client manager,
+not a missing or broken tool:
+
+- The tool can be present and registered in the Python `FastMCP` tool manager.
+- Direct Python inspection of the server confirms the tool exists.
+- Running the server manually and sending JSON-RPC over stdio works fine
+  (offline spawn) — that path does **not** prove the IDE namespace is healthy.
+
+The client manager entered a closed state after the backing subprocess for that
+namespace terminated (or was killed) behind its back. Once closed, the client
+does **not** re-spawn the child on the next tool call — it just replays
+`client is closing: EOF`. The OS process may even still be alive if a parent
+language-server process is holding the stdio pipes open.
+
+This is the canonical "registered in FastMCP ≠ callable through the namespace"
+false-ready state. It is distinct from the **stale-runtime** family in #531 /
+#544, where the process is reachable but running behind `master`; that case is
+detected by the `ps`-based `_check_mcp_runtimes_diagnostics` in
+`gitea_mcp_server.py`. The EOF case is a dead/closed transport, not a stale one,
+so the `ps` check alone will not surface it.
+
+## Recovery path (canonical — client reconnect only)
+
+Do the steps in order. Stop as soon as a live **client-namespace** call succeeds.
+
+1. **Confirm the blast radius.** Call a cheap read tool on the failing namespace
+   (`gitea_whoami` or `gitea_list_profiles`). Then call the same tool on a
+   different MCP server (e.g. `context7`).
+   - Only the Gitea namespace fails → single-namespace transport close. Continue.
+   - Every server fails → restart the whole MCP client, not just one namespace.
+
+2. **Reconnect the namespace through the client, not the shell.** Use the IDE /
+   client MCP-reconnect action for that server entry (in Claude Code:
+   `/mcp` → reconnect the affected `gitea-*` server). Reconnecting forces the
+   client to spawn a fresh subprocess and re-open the pipe. This clears the
+   closed-client state that a bare `kill`/respawn from a terminal does **not**.
+
+3. **Do not "fix" it by importing the server or poking the process.** Reaching
+   for `python -c 'import gitea_mcp_server ...'`, raw JSON-RPC from a shell,
+   killing PIDs to force a respawn, or touching MCP config mtimes does **not**
+   restore the *client's* view of the namespace and violates the daemon-import
+   guard (#558, `docs/mcp-daemon-import-guard.md`). The only sanctioned repair
+   is a **client reconnect / relaunch**.
+
+4. **Verify through the same path the workflow will use.** After reconnect, call
+   the specific tool the blocked workflow needs — not just any tool — through
+   the target namespace. For a merge that means calling the merger-authorized
+   adoption/merge tool through `gitea-merger`. A green `gitea_whoami` on one
+   namespace does **not** prove another namespace or another tool is callable.
+   Record success with:
+
+   ```text
+   gitea_assess_mcp_namespace_health(..., probe_source="client_namespace")
+   ```
+
+5. **If reconnect does not clear it,** relaunch the client entirely, then repeat
+   step 4. If EOF persists after a full relaunch, the backing subprocess is
+   failing to start — inspect its stderr / launch config (command path, venv,
+   `*_MCP_CONFIG`, `*_MCP_PROFILE` env) rather than retrying the call. Still
+   do not use PID kill or config-touch as the primary recovery.
+
+## Diagnostics to capture when reporting EOF
+
+Include all of these so the failure is actionable and reproducible:
+
+- **Namespace name** that returned EOF (`gitea-author` / `gitea-reviewer` /
+  `gitea-merger` / `gitea-tools`).
+- **Tool** that was called and the **exact** error string.
+- **PID** of the backing process (if any) and whether it was still alive
+  (informational only — not a recovery action).
+- **Profile / env** for that namespace (execution profile, `*_MCP_PROFILE`,
+  worktree binding such as `GITEA_AUTHOR_WORKTREE`).
+- **Config path** the client launched the server from.
+- Result of the **cross-server control** call (did `context7` succeed?).
+
+## Offline spawn probe (non-authoritative)
+
+`test_mcp_conn.py` performs a full JSON-RPC handshake against a **fresh
+subprocess** (`initialize` → `initialized` → `tools/list` → `tools/call`) and
+classifies with `probe_source=offline_spawn`. That is useful for offline
+launch/registration debugging. It is **not** proof the IDE-managed namespace is
+healthy. See `docs/mcp-namespace-health.md`.
+
+## Do-not list during EOF recovery
+
+- Do **not** retry a blocked merge/adoption until the required tool is confirmed
+  callable through the merger-authorized **client** namespace (see #543).
+- Do **not** clean, reset, or rebind a **foreign** worktree to work around the
+  error.
+- Do **not** bypass the namespace with direct imports, raw API/curl, or
+  in-memory state restoration.
+- Do **not** kill MCP PIDs or touch config mtimes as a substitute for client
+  reconnect.
+
+## Related
+
+- #531 / #544 — stale-runtime detection (`ps`-based); sibling failure mode.
+- #558 / `docs/mcp-daemon-import-guard.md` — why shell imports are not a repair.
+- `docs/mcp-client-registration.md` — per-server registration contract.
+- `docs/mcp-namespace-health.md` — probe sources and mutation enforcement.

docs/mcp-namespace-health.md

@@ -0,0 +1,88 @@
+# MCP namespace health diagnostics (#543)
+
+Gitea MCP tools can be registered in the Python FastMCP server while the IDE's
+live MCP namespace is still unusable. The failure usually appears as
+`client is closing: EOF`, `transport closed`, or an empty response when calling
+a tool such as `gitea_whoami`.
+
+Do not treat static tool registration as proof that review or merge workflows
+can proceed. A reviewer or merger flow must have **client-namespace** evidence
+that the required tool is callable through the configured IDE MCP namespace.
+
+## Probe sources (do not confuse them)
+
+| Source | How obtained | Proves IDE namespace? |
+| --- | --- | --- |
+| `client_namespace` | Tool call through the IDE-managed MCP client | **Yes** |
+| `offline_spawn` | `test_mcp_conn.py` subprocess JSON-RPC handshake | **No** (offline only) |
+
+`gitea_assess_mcp_namespace_health` accepts `probe_source` and only sets
+`ide_namespace_proven=true` for `client_namespace` success. Offline spawn
+success never clears review/merge mutation gates.
+
+## Client-namespace health check (canonical)
+
+1. Through the IDE client, call a cheap tool on the target namespace
+   (`gitea_whoami` or `gitea_list_profiles`).
+2. Feed the live result into:
+
+```text
+gitea_assess_mcp_namespace_health(
+    namespace="gitea-merger",          # or reviewer / author / tools
+    registered_tools=[...],            # optional static list
+    probe_result={"success": true, "result": {...}},
+    probe_source="client_namespace",
+)
+```
+
+3. A healthy client-namespace assessment is recorded in the MCP session and
+   consulted by **live** `gitea_submit_pr_review` / `gitea_merge_pr` gates.
+4. If the probe fails with EOF, recover via **client reconnect only** — see
+   `docs/mcp-namespace-eof-recovery.md`. Do **not** kill PIDs or touch MCP
+   config mtimes as a recovery procedure.
+
+## Offline spawn probe (non-authoritative)
+
+```bash
+python3 test_mcp_conn.py --config ~/.gemini/config/mcp_config.json
+```
+
+This script spawns a **separate** server process from config, performs
+JSON-RPC `initialize` → `tools/list` → `tools/call`, and classifies the
+result with `probe_source=offline_spawn`. Use it for offline debugging of
+launch command / registration. It does **not** prove the IDE-managed
+namespace is healthy.
+
+By default the script checks:
+
+| Namespace | Required tool |
+| --- | --- |
+| `gitea-author` | `gitea_whoami` |
+| `gitea-reviewer` | `gitea_whoami` |
+| `gitea-merger` | `gitea_whoami` |
+| `gitea-tools` | `gitea_list_profiles` |
+
+## Recovery (canonical)
+
+When a namespace returns EOF, follow
+`docs/mcp-namespace-eof-recovery.md` in order:
+
+1. Confirm blast radius (Gitea namespace vs all MCP servers).
+2. **Reconnect the namespace through the client** (IDE reconnect / relaunch).
+3. Do not repair via shell imports, raw JSON-RPC, PID kills, or config mtime
+   touches — those do not restore the client's closed transport.
+4. Re-verify the **specific** required tool through the target namespace.
+5. Resume review/merge only after a successful `client_namespace` assessment.
+
+## Enforcement
+
+1. **State machine (read-only):** feed `blocks_merge_workflow` from a
+   `client_namespace` assessment into
+   `gitea_assess_review_merge_state_machine(live_namespace_broken=...)`.
+2. **Live mutations:** `gitea_submit_pr_review` and `gitea_merge_pr` call
+   `_live_namespace_health_gate` and fail closed when the session has a
+   recorded unhealthy or non-client probe for the required namespace
+   (`gitea-reviewer` for review, `gitea-merger` for merge).
+
+When blocked, repair the IDE namespace and re-record a healthy
+`client_namespace` assessment before retrying the mutation.

gitea_mcp_server.py

@@ -191,6 +191,7 @@ MERGER_WORKTREE_ENV = "GITEA_MERGER_WORKTREE"
 RECONCILER_WORKTREE_ENV = "GITEA_RECONCILER_WORKTREE"
 
 import namespace_workspace_binding as nwb  # noqa: E402
+import mcp_namespace_health  # noqa: E402
 
 
 def _preflight_in_test_mode() -> bool:
@@ -1366,8 +1367,26 @@ def cleanup_in_progress_for_pr(pr_payload: dict, remote: str, host: str | None,
 
 # ── Helpers ───────────────────────────────────────────────────────────────────
 
+def _effective_remote(remote: str) -> str:
+    """If remote is the default ('dadeschools') but the active profile base_url maps to a known remote, use that remote instead."""
+    try:
+        profile = get_profile()
+        base_url = profile.get("base_url")
+        if remote == "dadeschools" and base_url:
+            import urllib.parse
+            url = urllib.parse.urlparse(base_url)
+            host = (url.netloc or url.path or "").strip().lower()
+            for k, v in REMOTES.items():
+                if v.get("host") == host:
+                    return k
+    except Exception:
+        pass
+    return remote
+
+
 def _resolve(remote: str, host: str | None, org: str | None, repo: str | None):
     """Resolve remote + overrides to (host, org, repo)."""
+    remote = _effective_remote(remote)
     if remote not in REMOTES:
         raise ValueError(f"Unknown remote '{remote}'. Choose from: {list(REMOTES)}")
     profile = REMOTES[remote]
@@ -1401,6 +1420,7 @@ def _resolve_control_plane_guide_target(
     if org is not None and repo is not None:
         return _resolve(remote, host, org, repo)
 
+    remote = _effective_remote(remote)
     if remote not in REMOTES:
         raise ValueError(f"Unknown remote '{remote}'. Choose from: {list(REMOTES)}")
 
@@ -2824,6 +2844,35 @@ _TERMINAL_REVIEW_ACTIONS = frozenset({"approve", "request_changes"})
 # remote + profile identity with TTL.
 _REVIEW_DECISION_LOCK: dict | None = None
 
+# Session-scoped live MCP namespace health assessments (#543).
+# Keyed by namespace name. Only client_namespace entries authorize mutations.
+_LIVE_NAMESPACE_HEALTH: dict[str, dict] = {}
+
+
+def _record_live_namespace_health(assessment: dict | None) -> None:
+    """Store a namespace health assessment for mutation gates."""
+    if not isinstance(assessment, dict):
+        return
+    ns = str(assessment.get("namespace") or "").strip()
+    if not ns:
+        return
+    _LIVE_NAMESPACE_HEALTH[ns] = {
+        "namespace": ns,
+        "healthy": bool(assessment.get("healthy")),
+        "ide_namespace_proven": bool(assessment.get("ide_namespace_proven")),
+        "probe_source": assessment.get("probe_source"),
+        "blocks_merge_workflow": bool(assessment.get("blocks_merge_workflow")),
+        "error_type": assessment.get("error_type"),
+        "required_tool": assessment.get("required_tool"),
+    }
+
+
+def _live_namespace_health_gate(task: str) -> list[str]:
+    """Fail closed on recorded broken/non-client IDE namespace health (#543)."""
+    return mcp_namespace_health.mutation_gate_from_session(
+        task, _LIVE_NAMESPACE_HEALTH
+    )
+
 
 def _decision_lock_binding(lock: dict | None = None) -> dict:
     """Resolve key fields for durable decision-lock storage."""
@@ -3046,22 +3095,26 @@ def check_review_decision_gate(
         )
 
     prior = list(lock.get("live_mutations") or [])
-    if prior and not lock.get("correction_authorized"):
-        reasons.append(
-            "live review mutation already recorded in this run; only one live "
-            "review mutation is allowed unless "
-            "gitea_authorize_review_correction was invoked (fail closed)"
-        )
-    elif (
-        action in _TERMINAL_REVIEW_ACTIONS
-        and any(m.get("action") in _TERMINAL_REVIEW_ACTIONS for m in prior)
-        and not lock.get("correction_authorized")
+    ready_head = lock.get("ready_expected_head_sha")
+    if stale_review_decision_lock.prior_live_mutations_block_boundary(
+        lock, pr_number=pr_number, expected_head_sha=ready_head
     ):
-        reasons.append(
-            "terminal review decision already submitted on this PR in this "
-            "run; blocked unless an operator-approved correction was "
-            "authorized (fail closed)"
-        )
+        if prior and not lock.get("correction_authorized"):
+            reasons.append(
+                "live review mutation already recorded for this PR head in this "
+                "run; only one live review mutation is allowed per head unless "
+                "gitea_authorize_review_correction was invoked (fail closed, #620)"
+            )
+        elif (
+            action in _TERMINAL_REVIEW_ACTIONS
+            and any(m.get("action") in _TERMINAL_REVIEW_ACTIONS for m in prior)
+            and not lock.get("correction_authorized")
+        ):
+            reasons.append(
+                "terminal review decision already submitted for this PR head in "
+                "this run; blocked unless an operator-approved correction was "
+                "authorized (fail closed, #620)"
+            )
 
     return reasons
 
@@ -3069,12 +3122,18 @@ def check_review_decision_gate(
 def record_live_review_mutation(pr_number: int, action: str, review_id: int | None = None):
     lock = _load_review_decision_lock() or {}
     mutations = list(lock.get("live_mutations") or [])
-    mutations.append({
+    head_sha = stale_review_decision_lock.normalize_head_sha(
+        lock.get("ready_expected_head_sha")
+    )
+    entry = {
         "pr_number": pr_number,
         "action": action,
         "review_id": review_id,
         "review_state": action,
-    })
+    }
+    if head_sha:
+        entry["head_sha"] = head_sha
+    mutations.append(entry)
     lock["live_mutations"] = mutations
     if lock.get("correction_authorized"):
         lock["correction_authorized"] = False
@@ -3082,17 +3141,28 @@ def record_live_review_mutation(pr_number: int, action: str, review_id: int | No
     _save_review_decision_lock(lock)
 
 
-def terminal_review_hard_stop_reasons(pr_number: int, operation: str) -> list[str]:
-    """Session hard-stop after a terminal live review mutation (#332).
+def terminal_review_hard_stop_reasons(
+    pr_number: int,
+    operation: str,
+    expected_head_sha: str | None = None,
+) -> list[str]:
+    """Session hard-stop after a terminal live review mutation (#332 / #620).
 
-    After a terminal verdict is consumed in this run, the only permitted
-    continuation is the merge sequence for the same PR that was approved.
-    A REQUEST_CHANGES (or an approval of a different PR) blocks every
-    further review/mark-ready/merge mutation. An operator-approved
-    correction (#211) re-opens the review path only — never a cross-PR
-    merge.
+    After a terminal verdict is consumed for a given PR **head**, the only
+    permitted continuation is the merge sequence for that same approved PR
+    (merge does not require a new head). A REQUEST_CHANGES (or an approval of
+    a different PR, or the same head) blocks further review/mark-ready/merge
+    mutations for that boundary.
 
-    *operation* is one of 'merge', 'mark_ready', or 'review'.
+    #620: when *expected_head_sha* differs from the last terminal's reviewed
+    head on the **same open PR**, mark_ready / review / resume may proceed so
+    a fresh formal decision can be recorded for the new head. Historical
+    mutations are preserved.
+
+    An operator-approved correction (#211) re-opens the review path only —
+    never a cross-PR merge.
+
+    *operation* is one of 'merge', 'mark_ready', 'review', or 'resume'.
     Returns [] when the operation may proceed.
     """
     lock = _load_review_decision_lock()
@@ -3111,8 +3181,19 @@ def terminal_review_hard_stop_reasons(pr_number: int, operation: str) -> list[st
         and last.get("pr_number") == pr_number
     ):
         return []
-    if operation in ("mark_ready", "review") and lock.get("correction_authorized"):
+    if operation in ("mark_ready", "review", "resume") and lock.get(
+        "correction_authorized"
+    ):
         return []
+    # #620: same PR, different reviewed head → fresh decision boundary.
+    if stale_review_decision_lock.terminal_boundary_allows_fresh_decision(
+        lock,
+        pr_number=pr_number,
+        expected_head_sha=expected_head_sha,
+        operation=operation,
+    ):
+        return []
+    locked_head = stale_review_decision_lock.mutation_head_sha(last, lock)
     if last.get("action") == "approve":
         guidance = (
             f"only the merge sequence for approved PR "
@@ -3120,15 +3201,22 @@ def terminal_review_hard_stop_reasons(pr_number: int, operation: str) -> list[st
         )
     else:
         guidance = "the session must stop and produce a final report"
+    head_note = (
+        f" at head {locked_head[:12]}…"
+        if locked_head
+        else ""
+    )
     recovery = (
         "if that PR is already merged/closed, use "
         "gitea_cleanup_stale_review_decision_lock (apply=true) after live-state "
-        "proof (#594); never delete session-state files by hand"
+        "proof (#594); if the PR is still open but the head moved, mark/submit "
+        "with the new expected_head_sha (#620); never delete session-state "
+        "files by hand"
     )
     return [
         "terminal review mutation already consumed in this run "
-        f"({last.get('action')} on PR #{last.get('pr_number')}); {guidance} "
-        f"(fail closed, #332); {recovery}"
+        f"({last.get('action')} on PR #{last.get('pr_number')}{head_note}); "
+        f"{guidance} (fail closed, #332); {recovery}"
     ]
 
 
@@ -3514,6 +3602,11 @@ def _evaluate_pr_review_submission(
         reasons.extend(workflow_blockers)
         reasons.extend(review_workflow_load.recovery_handoff_without_replay())
         return result
+    if live:
+        ns_gate = _live_namespace_health_gate("review_pr")
+        if ns_gate:
+            reasons.extend(ns_gate)
+            return result
 
     if action not in _REVIEW_ACTIONS:
         reasons.append(
@@ -3746,18 +3839,11 @@ def gitea_mark_final_review_decision(
             "reasons": workflow_blockers + (
                 review_workflow_load.recovery_handoff_without_replay()),
         }
-    hard_stop = terminal_review_hard_stop_reasons(pr_number, "mark_ready")
+    hard_stop = terminal_review_hard_stop_reasons(
+        pr_number, "mark_ready", expected_head_sha=expected_head_sha
+    )
     if hard_stop:
         return {"marked_ready": False, "reasons": hard_stop}
-    if lock.get("live_mutations") and not lock.get("correction_authorized"):
-        return {
-            "marked_ready": False,
-            "reasons": [
-                "cannot mark final decision after a live review mutation was "
-                "already recorded in this run unless an operator-approved "
-                "correction was authorized"
-            ],
-        }
     if action not in _REVIEW_ACTIONS:
         return {
             "marked_ready": False,
@@ -3774,6 +3860,17 @@ def gitea_mark_final_review_decision(
                 "decision (fail closed, #399)"
             ],
         }
+    if stale_review_decision_lock.prior_live_mutations_block_boundary(
+        lock, pr_number=pr_number, expected_head_sha=expected_head_sha
+    ):
+        return {
+            "marked_ready": False,
+            "reasons": [
+                "cannot mark final decision after a live review mutation was "
+                "already recorded for this PR head unless an operator-approved "
+                "correction was authorized (fail closed, #620)"
+            ],
+        }
     elig = gitea_check_pr_eligibility(
         pr_number=pr_number,
         action="review",
@@ -3826,6 +3923,8 @@ def gitea_mark_final_review_decision(
                     "#332)"
                 ],
             }
+    # Preserve historical terminal head boundaries before advancing ready_* (#620).
+    stale_review_decision_lock.backfill_terminal_heads_from_ready(lock)
     lock["final_review_decision_ready"] = True
     lock["ready_pr_number"] = pr_number
     lock["ready_action"] = action
@@ -3843,6 +3942,7 @@ def gitea_mark_final_review_decision(
         "org": org,
         "repo": repo,
         "final_review_decision_ready": True,
+        "head_scoped": True,
         "reasons": [],
     }
 
@@ -4009,6 +4109,12 @@ def gitea_cleanup_stale_review_decision_lock(
         "cleanup_allowed": assessment.get("cleanup_allowed"),
         "last_terminal_pr": assessment.get("last_terminal_pr"),
         "last_terminal_action": assessment.get("last_terminal_action"),
+        "locked_head_sha": assessment.get("locked_head_sha"),
+        "current_pr_head_sha": assessment.get("current_pr_head_sha"),
+        "stale_by_head": assessment.get("stale_by_head"),
+        "fresh_review_on_current_head_allowed": assessment.get(
+            "fresh_review_on_current_head_allowed"
+        ),
         "pr_state": assessment.get("pr_state"),
         "pr_merged": assessment.get("pr_merged"),
         "pr_merged_or_closed": assessment.get("pr_merged_or_closed"),
@@ -4162,6 +4268,335 @@ def gitea_submit_pr_review(
     )
 
 
+@mcp.tool()
+def gitea_save_review_draft(
+    pr_number: int,
+    action: str,
+    body: str = "",
+    expected_head_sha: str | None = None,
+    validation_commands: str | None = None,
+    validation_results: str | None = None,
+    blocker_reason: str | None = None,
+    remote: str = "dadeschools",
+    host: str | None = None,
+    org: str | None = None,
+    repo: str | None = None,
+    worktree_path: str | None = None,
+) -> dict:
+    """Save a prepared review verdict as non-terminal draft evidence without submitting a formal review.
+
+    This permits resuming the review later (e.g. after a stale runtime restart or connection drop).
+    """
+    action = (action or "").strip().lower()
+    if action not in _REVIEW_ACTIONS:
+        return {
+            "success": False,
+            "reasons": [
+                f"unknown review action '{action}'; expected one of "
+                f"{sorted(_REVIEW_ACTIONS)}"
+            ],
+        }
+
+    # 1. Resolve remote context
+    try:
+        h, resolved_org, resolved_repo = _resolve(remote, host, org, repo)
+    except ValueError as exc:
+        return {"success": False, "reasons": [str(exc)]}
+
+    auth = _auth(h)
+
+    # 2. Fetch current PR details to get target base branch and base branch SHA
+    try:
+        pr_url = f"{repo_api_url(h, resolved_org, resolved_repo)}/pulls/{pr_number}"
+        pr = api_request("GET", pr_url, auth) or {}
+    except Exception as exc:
+        return {
+            "success": False,
+            "reasons": [f"failed to fetch PR #{pr_number} from Gitea: {str(exc)}"],
+        }
+
+    current_head = (pr.get("head") or {}).get("sha")
+    target_branch = (pr.get("base") or {}).get("ref")
+    target_branch_sha = (pr.get("base") or {}).get("sha")
+
+    if expected_head_sha and current_head and expected_head_sha != current_head:
+        return {
+            "success": False,
+            "reasons": [
+                f"expected_head_sha '{expected_head_sha}' does not match current PR head SHA '{current_head}'"
+            ],
+        }
+
+    # 3. Resolve worktree path
+    try:
+        resolved_worktree = _resolve_preflight_workspace_path(worktree_path)
+    except Exception as exc:
+        return {"success": False, "reasons": [f"failed to resolve worktree path: {str(exc)}"]}
+
+    # 4. Save payload to durable session state
+    profile = get_profile()
+    payload = {
+        "pr_number": pr_number,
+        "action": action,
+        "body": body,
+        "head_sha": expected_head_sha or current_head,
+        "target_branch": target_branch,
+        "target_branch_sha": target_branch_sha,
+        "worktree_path": resolved_worktree,
+        "validation_commands": validation_commands,
+        "validation_results": validation_results,
+        "blocker_reason": blocker_reason,
+        "saved_by_identity": _authenticated_username(h) or "",
+        "saved_by_profile": profile.get("profile_name"),
+        "remote": remote,
+        "org": resolved_org,
+        "repo": resolved_repo,
+    }
+
+    try:
+        mcp_session_state.save_state(
+            kind=mcp_session_state.KIND_REVIEW_DRAFT,
+            payload=payload,
+            remote=remote,
+            org=resolved_org,
+            repo=resolved_repo,
+            profile_identity=profile.get("profile_name"),
+        )
+    except Exception as exc:
+        return {"success": False, "reasons": [f"failed to save draft state: {str(exc)}"]}
+
+    return {
+        "success": True,
+        "pr_number": pr_number,
+        "action": action,
+        "head_sha": payload["head_sha"],
+        "target_branch": target_branch,
+        "target_branch_sha": target_branch_sha,
+        "worktree_path": resolved_worktree,
+    }
+
+
+@mcp.tool()
+def gitea_resume_review_draft(
+    pr_number: int,
+    submit: bool = False,
+    remote: str = "dadeschools",
+    host: str | None = None,
+    org: str | None = None,
+    repo: str | None = None,
+    worktree_path: str | None = None,
+) -> dict:
+    """Resume a previously saved review draft for the given PR number.
+
+    Performs live-state checks (PR head SHA, target branch SHA, terminal lock, active leases,
+    runtime/master parity, reviewer identity, worktree binding, validation freshness).
+    Refuses to submit or mark ready if any state has changed unsafely.
+    """
+    profile = get_profile()
+    active_profile = profile.get("profile_name")
+
+    # 1. Load draft state
+    try:
+        draft = mcp_session_state.load_state(
+            kind=mcp_session_state.KIND_REVIEW_DRAFT,
+            remote=remote,
+            org=org,
+            repo=repo,
+            profile_identity=active_profile,
+        )
+    except Exception as exc:
+        return {"success": False, "reasons": [f"failed to load draft state: {str(exc)}"]}
+
+    if not draft:
+        return {
+            "success": False,
+            "reasons": [f"no review draft found for PR #{pr_number} under profile '{active_profile}'"],
+        }
+
+    if draft.get("pr_number") != pr_number:
+        return {
+            "success": False,
+            "reasons": [
+                f"loaded draft is for PR #{draft.get('pr_number')}, but requested PR #{pr_number}"
+            ],
+        }
+
+    # 2. Resolve remote context
+    try:
+        h, resolved_org, resolved_repo = _resolve(remote, host, org, repo)
+    except ValueError as exc:
+        return {"success": False, "reasons": [str(exc)]}
+
+    auth = _auth(h)
+
+    # 3. Fetch live PR state
+    try:
+        pr_url = f"{repo_api_url(h, resolved_org, resolved_repo)}/pulls/{pr_number}"
+        pr = api_request("GET", pr_url, auth) or {}
+    except Exception as exc:
+        return {
+            "success": False,
+            "reasons": [f"failed to fetch PR #{pr_number} from Gitea: {str(exc)}"],
+        }
+
+    # 4. Perform live-state checks
+    reasons = []
+
+    # PR must be open
+    if pr.get("state") != "open":
+        reasons.append(f"PR #{pr_number} is not open (state: '{pr.get('state')}')")
+
+    # Live head SHA must match saved head_sha
+    live_head = (pr.get("head") or {}).get("sha")
+    saved_head = draft.get("head_sha")
+    if live_head != saved_head:
+        reasons.append(
+            f"PR head SHA changed (live={live_head!r}, saved={saved_head!r})"
+        )
+
+    # Live target branch SHA must match saved target_branch_sha
+    live_target_sha = (pr.get("base") or {}).get("sha")
+    saved_target_sha = draft.get("target_branch_sha")
+    if live_target_sha != saved_target_sha:
+        reasons.append(
+            f"target branch SHA changed (live={live_target_sha!r}, saved={saved_target_sha!r})"
+        )
+
+    # Check #332 terminal lock
+    hard_stop = terminal_review_hard_stop_reasons(pr_number, "resume")
+    if hard_stop:
+        reasons.extend(hard_stop)
+
+    # Check active reviewer lease (must be claimed by the current session)
+    try:
+        comments = _fetch_pr_comments(pr_number, remote=remote, host=host, org=resolved_org, repo=resolved_repo)
+    except Exception as exc:
+        reasons.append(f"failed to fetch PR comments: {str(exc)}")
+        comments = []
+
+    active_lease = reviewer_pr_lease.find_active_reviewer_lease(comments, pr_number=pr_number)
+    if not active_lease:
+        reasons.append(f"no active reviewer lease found on PR #{pr_number}")
+    else:
+        # Check that lease owner is our session_id
+        session = reviewer_pr_lease.get_session_lease()
+        session_id = (session or {}).get("session_id")
+        owner_session_id = active_lease.get("session_id")
+        if owner_session_id != session_id:
+            reasons.append(
+                f"active reviewer lease belongs to session_id={owner_session_id!r}, "
+                f"but current session has session_id={session_id!r}"
+            )
+
+    # Check runtime/master parity
+    if "PYTEST_CURRENT_TEST" not in os.environ or "GITEA_FORCE_MCP_RUNTIME_CHECK" in os.environ:
+        config = gitea_config.load_config()
+        matching_profiles = []
+        if config and "profiles" in config:
+            for p_name, p_data in config["profiles"].items():
+                p_allowed = p_data.get("allowed_operations") or []
+                p_forbidden = p_data.get("forbidden_operations") or []
+                p_allowed_n = []
+                for op in p_allowed:
+                    try:
+                        p_allowed_n.append(gitea_config.normalize_operation(op))
+                    except Exception:
+                        pass
+                p_forbidden_n = []
+                for op in p_forbidden:
+                    try:
+                        p_forbidden_n.append(gitea_config.normalize_operation(op))
+                    except Exception:
+                        pass
+                # Check for "review_pr" or similar capability
+                ok, _ = gitea_config.check_operation("gitea.pr.review", p_allowed_n, p_forbidden_n)
+                if ok:
+                    matching_profiles.append(p_name)
+        runtime_reasons = _check_mcp_runtimes_diagnostics("review_pr", matching_profiles)
+        if runtime_reasons:
+            reasons.extend(runtime_reasons)
+
+    # Check reviewer identity
+    identity = _authenticated_username(h)
+    if identity != draft.get("saved_by_identity"):
+        reasons.append(
+            f"reviewer identity mismatch (active={identity!r}, saved={draft.get('saved_by_identity')!r})"
+        )
+
+    # Check worktree binding
+    try:
+        resolved_worktree = _resolve_preflight_workspace_path(worktree_path)
+    except Exception as exc:
+        reasons.append(f"failed to resolve current worktree: {str(exc)}")
+        resolved_worktree = None
+    if resolved_worktree != draft.get("worktree_path"):
+        reasons.append(
+            f"worktree binding mismatch (current={resolved_worktree!r}, saved={draft.get('worktree_path')!r})"
+        )
+
+    if reasons:
+        return {"success": False, "reasons": reasons}
+
+    # 5. All checks pass! Mark decision lock as ready.
+    action = draft.get("action")
+    body = draft.get("body")
+    saved_head = draft.get("head_sha")
+
+    lock = _load_review_decision_lock() or {}
+    lock["final_review_decision_ready"] = True
+    lock["ready_pr_number"] = pr_number
+    lock["ready_action"] = action
+    lock["ready_expected_head_sha"] = saved_head
+    lock["ready_remote"] = remote
+    lock["ready_org"] = resolved_org
+    lock["ready_repo"] = resolved_repo
+    _save_review_decision_lock(lock)
+
+    submitted = False
+    submission_res = None
+    if submit:
+        # Submit the review!
+        submission_res = gitea_submit_pr_review(
+            pr_number=pr_number,
+            action=action,
+            body=body,
+            expected_head_sha=saved_head,
+            remote=remote,
+            host=host,
+            org=resolved_org,
+            repo=resolved_repo,
+            final_review_decision_ready=True,
+            worktree_path=resolved_worktree,
+        )
+        if submission_res.get("performed") or submission_res.get("success"):
+            submitted = True
+            # Delete the draft payload on success
+            mcp_session_state.save_state(
+                kind=mcp_session_state.KIND_REVIEW_DRAFT,
+                payload=None,
+                remote=remote,
+                org=resolved_org,
+                repo=resolved_repo,
+                profile_identity=active_profile,
+            )
+        else:
+            # If submit fails, return the submit failure reasons
+            return {
+                "success": False,
+                "reasons": submission_res.get("reasons") or ["submission failed"],
+                "submission_result": submission_res,
+            }
+
+    return {
+        "success": True,
+        "pr_number": pr_number,
+        "action": action,
+        "marked_ready": True,
+        "submitted": submitted,
+        "submission_result": submission_res,
+    }
+
+
 @mcp.tool()
 def gitea_edit_pr(
     pr_number: int,
@@ -4615,6 +5050,12 @@ def gitea_merge_pr(
         reasons.extend(review_workflow_load.recovery_handoff_without_replay())
         return result
 
+    # Gate 0b — recorded live MCP namespace health must not be broken (#543).
+    ns_gate = _live_namespace_health_gate("merge_pr")
+    if ns_gate:
+        reasons.extend(ns_gate)
+        return result
+
     # Gate 1 — valid merge method (no API call on a bad method).
     if do not in _MERGE_METHODS:
         reasons.append(
@@ -8380,6 +8821,7 @@ def gitea_whoami(
         metadata: profile_name + allowed_operations; never the token).
     """
     record_preflight_check("whoami")
+    remote = _effective_remote(remote)
     if remote not in REMOTES:
         raise ValueError(f"Unknown remote '{remote}'. Choose from: {list(REMOTES)}")
     h = host or REMOTES[remote]["host"]
@@ -8488,8 +8930,6 @@ def gitea_get_profile(
         "execution_profile": profile.get("execution_profile"),
         "auth_source_type": profile.get("auth_source_type"),
         # Auth is reported as a status only (#120): the token source *name*
-        # (env var name / keychain id) joins endpoint URLs behind the
-        # GITEA_MCP_REVEAL_ENDPOINTS admin opt-in. Token values never appear.
         "auth_status": ("configured" if profile["token_source_name"]
                         else "unconfigured"),
         "remote": remote if remote in REMOTES else None,
@@ -8501,6 +8941,7 @@ def gitea_get_profile(
         result["base_url"] = profile["base_url"]
         result["server"] = None
 
+    remote = _effective_remote(remote)
     if remote not in REMOTES:
         # Mark ambiguity rather than raising: the tool stays inspectable.
         result["identity_status"] = "unknown"
@@ -8624,40 +9065,45 @@ def gitea_assess_review_merge_state_machine(
     pre_merge_gates: dict[str, bool] | None = None,
     infra_stop: bool = False,
     capability_blocked: bool = False,
+    live_namespace_broken: bool = False,
     recovery_handoff_text: str | None = None,
     final_report_text: str | None = None,
 ) -> dict:
-    """Read-only: assess enforced PR review/merge workflow state (#290)."""
+    """Read-only: assess enforced PR review/merge workflow state (#290).
+
+    ``live_namespace_broken`` fails review/merge closed when the live MCP
+    namespace call path is unusable even though the tool is registered in
+    FastMCP (#543 AC5). Supply the ``blocks_merge_workflow`` verdict from
+    ``gitea_assess_mcp_namespace_health``.
+    """
     completion = state_completion or {}
-    blockers = review_merge_state_machine.assess_workflow_blockers(
-        infra_stop=infra_stop,
-        capability_blocked=capability_blocked,
-    )
+    blocker_kwargs = {
+        "infra_stop": infra_stop,
+        "capability_blocked": capability_blocked,
+        "live_namespace_broken": live_namespace_broken,
+    }
+    blockers = review_merge_state_machine.assess_workflow_blockers(**blocker_kwargs)
     result = {
         "workflow": review_merge_state_machine.workflow_status(
             completion,
-            infra_stop=infra_stop,
-            capability_blocked=capability_blocked,
+            **blocker_kwargs,
         ),
         "blockers": blockers,
         "approve": review_merge_state_machine.can_approve(
             completion,
-            infra_stop=infra_stop,
-            capability_blocked=capability_blocked,
+            **blocker_kwargs,
         ),
         "merge": review_merge_state_machine.can_merge(
             completion,
             pre_merge_gates=pre_merge_gates,
-            infra_stop=infra_stop,
-            capability_blocked=capability_blocked,
+            **blocker_kwargs,
         ),
     }
     if target_state:
         result["advancement"] = review_merge_state_machine.assess_state_advancement(
             completion,
             target_state=target_state,
-            infra_stop=infra_stop,
-            capability_blocked=capability_blocked,
+            **blocker_kwargs,
         )
     if recovery_handoff_text is not None:
         result["recovery_handoff"] = (
@@ -9187,6 +9633,46 @@ def gitea_list_profiles() -> dict:
     return {"profiles": profiles_out}
 
 
+@mcp.tool()
+def gitea_assess_mcp_namespace_health(
+    namespace: str,
+    required_tool: str | None = None,
+    registered_tools: list[str] | None = None,
+    probe_result: dict | None = None,
+    process: dict | None = None,
+    config_path: str | None = None,
+    profile: str | None = None,
+    configured: bool = True,
+    probe_source: str | None = None,
+) -> dict:
+    """Classify MCP namespace health for required Gitea tools (#543).
+
+    Static FastMCP registration is not enough to prove a namespace works: IDE
+    clients can keep a registered tool list while live calls fail with
+    ``client is closing: EOF``. Pass live IDE invocation evidence with
+    ``probe_source='client_namespace'``. Offline subprocess probes
+    (``test_mcp_conn.py``) must use ``probe_source='offline_spawn'`` and never
+    count as IDE proof.
+
+    Assessments are recorded in the session so live
+    ``gitea_submit_pr_review`` / ``gitea_merge_pr`` can fail closed when a
+    client-namespace probe reported unhealthy.
+    """
+    result = mcp_namespace_health.classify_namespace_probe(
+        namespace,
+        required_tool=required_tool,
+        registered_tools=registered_tools,
+        probe_result=probe_result,
+        process=process,
+        config_path=config_path,
+        profile=profile,
+        configured=configured,
+        probe_source=probe_source,
+    )
+    _record_live_namespace_health(result)
+    return result
+
+
 @mcp.tool()
 def gitea_activate_profile(
     profile_name: str,

mcp_namespace_health.py

@@ -0,0 +1,306 @@
+"""Assess live MCP namespace health without trusting static registration.
+
+The IDE/client namespace can fail with EOF even when this Python process still
+registers the Gitea tools with FastMCP.  These helpers keep that distinction
+explicit so reviewer/merger flows can fail closed on the live path.
+
+Probe sources
+-------------
+* ``client_namespace`` — evidence from the IDE-managed MCP client path (the
+  only source that can prove the workflow namespace is healthy).
+* ``offline_spawn`` — a separate ``subprocess.Popen`` JSON-RPC handshake
+  (e.g. ``test_mcp_conn.py``). Useful offline, but **never** proves the
+  IDE-managed namespace is callable.
+* ``unknown`` — legacy/unspecified; treated as not IDE-proven.
+"""
+
+from __future__ import annotations
+
+from typing import Any
+
+
+REQUIRED_NAMESPACE_TOOLS = {
+    "gitea-author": "gitea_whoami",
+    "gitea-reviewer": "gitea_whoami",
+    "gitea-merger": "gitea_whoami",
+    "gitea-tools": "gitea_list_profiles",
+}
+
+DEFAULT_NAMESPACES = tuple(REQUIRED_NAMESPACE_TOOLS)
+
+# Namespaces that must be healthy for a given mutation task.
+TASK_REQUIRED_NAMESPACES = {
+    "review_pr": "gitea-reviewer",
+    "submit_review": "gitea-reviewer",
+    "merge_pr": "gitea-merger",
+}
+
+PROBE_SOURCE_CLIENT = "client_namespace"
+PROBE_SOURCE_OFFLINE = "offline_spawn"
+PROBE_SOURCE_UNKNOWN = "unknown"
+VALID_PROBE_SOURCES = frozenset(
+    {PROBE_SOURCE_CLIENT, PROBE_SOURCE_OFFLINE, PROBE_SOURCE_UNKNOWN}
+)
+
+EOF_PATTERNS = (
+    "client is closing: eof",
+    "transport closed",
+    "connection closed",
+    "broken pipe",
+    "end of file",
+    "eof",
+)
+
+SAFE_ENV_KEYS = (
+    "GITEA_MCP_PROFILE",
+    "GITEA_PROFILE_NAME",
+    "GITEA_SERVICE",
+    "GITEA_EXECUTION_ROLE",
+    "GITEA_MCP_CONFIG",
+)
+
+
+def _as_list(value: Any) -> list[str] | None:
+    if value is None:
+        return None
+    if isinstance(value, (list, tuple, set)):
+        return [str(v) for v in value]
+    return [str(value)]
+
+
+def _contains_eof(text: str | None) -> bool:
+    lowered = (text or "").lower()
+    return any(pattern in lowered for pattern in EOF_PATTERNS)
+
+
+def _normalize_probe_source(probe_source: str | None) -> str:
+    raw = (probe_source or PROBE_SOURCE_UNKNOWN).strip().lower()
+    if raw in VALID_PROBE_SOURCES:
+        return raw
+    return PROBE_SOURCE_UNKNOWN
+
+
+def _safe_env_summary(process: dict[str, Any] | None) -> dict[str, str]:
+    if not process:
+        return {}
+    env = process.get("env") or process.get("environment") or {}
+    if not isinstance(env, dict):
+        return {}
+    return {
+        key: str(env[key])
+        for key in SAFE_ENV_KEYS
+        if key in env and env[key] not in (None, "")
+    }
+
+
+def classify_namespace_probe(
+    namespace: str,
+    *,
+    required_tool: str | None = None,
+    registered_tools: list[str] | tuple[str, ...] | set[str] | None = None,
+    probe_result: dict[str, Any] | None = None,
+    process: dict[str, Any] | None = None,
+    config_path: str | None = None,
+    profile: str | None = None,
+    configured: bool = True,
+    probe_source: str | None = None,
+) -> dict[str, Any]:
+    """Classify whether a required tool is callable through a live namespace.
+
+    ``registered_tools`` is static/server-side evidence. ``probe_result`` is
+    live invocation evidence. Only ``probe_source=client_namespace`` proves the
+    IDE-managed path; ``offline_spawn`` is an offline subprocess check only.
+    """
+    ns = (namespace or "").strip()
+    tool = required_tool or REQUIRED_NAMESPACE_TOOLS.get(ns) or "gitea_whoami"
+    source = _normalize_probe_source(probe_source)
+    registered_list = _as_list(registered_tools)
+    registered = None if registered_list is None else tool in registered_list
+
+    probe = probe_result or {}
+    probe_success = bool(probe.get("success"))
+    error_message = str(
+        probe.get("error")
+        or probe.get("message")
+        or probe.get("stderr")
+        or probe.get("exception")
+        or ""
+    )
+    error_type = str(probe.get("error_type") or "").strip()
+    if not error_type and error_message:
+        if _contains_eof(error_message):
+            error_type = "namespace_eof"
+        elif "timeout" in error_message.lower():
+            error_type = "namespace_timeout"
+        else:
+            error_type = "namespace_call_failed"
+
+    if not configured:
+        error_type = "namespace_not_configured"
+    elif registered is False:
+        error_type = "tool_missing"
+    elif not probe_result:
+        error_type = "live_probe_missing"
+    elif not probe_success and not error_type:
+        error_type = "namespace_call_failed"
+
+    callable_live = bool(configured and probe_result and probe_success)
+    # Probe-path health (spawn or client). IDE-proven only for client path.
+    healthy = bool(configured and registered is not False and callable_live)
+    ide_namespace_proven = bool(healthy and source == PROBE_SOURCE_CLIENT)
+    process_pid = process.get("pid") if isinstance(process, dict) else None
+    profile_name = profile or (
+        process.get("profile") if isinstance(process, dict) else None
+    )
+    env_summary = _safe_env_summary(process)
+
+    reasons: list[str] = []
+    if not configured:
+        reasons.append(f"MCP namespace '{ns}' is not configured.")
+    if registered is False:
+        reasons.append(
+            f"Required tool '{tool}' is not registered in namespace '{ns}'."
+        )
+    if error_type == "live_probe_missing":
+        reasons.append(
+            f"No live client invocation proof was supplied for '{ns}.{tool}'."
+        )
+    elif error_type == "namespace_eof":
+        reasons.append(
+            f"Live MCP namespace '{ns}' returned EOF while invoking '{tool}'."
+        )
+    elif error_type == "namespace_timeout":
+        reasons.append(
+            f"Live MCP namespace '{ns}' timed out while invoking '{tool}'."
+        )
+    elif error_type == "namespace_call_failed":
+        reasons.append(
+            f"Live MCP namespace '{ns}' failed while invoking '{tool}'."
+        )
+    if source == PROBE_SOURCE_OFFLINE:
+        reasons.append(
+            "Probe source is offline_spawn (subprocess JSON-RPC); this does "
+            "not prove the IDE-managed MCP namespace is healthy."
+        )
+    elif source == PROBE_SOURCE_UNKNOWN and probe_result:
+        reasons.append(
+            "Probe source unspecified; treat as not IDE-namespace proof unless "
+            "re-supplied with probe_source='client_namespace'."
+        )
+
+    remediation = []
+    if not healthy or not ide_namespace_proven:
+        remediation.append(
+            "Reconnect the IDE MCP client namespace (client reconnect / "
+            f"relaunch), then invoke '{tool}' through namespace '{ns}' and "
+            "record the result with probe_source='client_namespace'."
+        )
+        remediation.append(
+            "Do not treat offline subprocess probes (test_mcp_conn.py) or "
+            "shell kill/PID respawn as proof the IDE namespace is repaired."
+        )
+        if process_pid and source != PROBE_SOURCE_OFFLINE:
+            remediation.append(
+                f"Diagnostics may include PID {process_pid}; process details "
+                "are informational only — recovery is client-layer reconnect."
+            )
+    else:
+        remediation.append(
+            f"IDE-managed namespace '{ns}' can invoke '{tool}' "
+            f"(probe_source={source})."
+        )
+
+    # Client-namespace broken health blocks review/merge. Offline probes never
+    # authorize mutations and only block when they report unhealthy (still
+    # fail-closed for known bad spawn evidence).
+    blocks = False
+    if source == PROBE_SOURCE_CLIENT:
+        blocks = namespace_health_blocks_task("merge_pr", healthy)
+    elif source == PROBE_SOURCE_OFFLINE:
+        # Offline never proves IDE health; never unblock. Unhealthy offline
+        # still surfaces as a soft diagnostic, not a mutation-ledger block.
+        blocks = False
+    else:
+        # Unknown source: only block when evidence is unhealthy (fail closed
+        # on bad data without treating success as IDE proof).
+        blocks = namespace_health_blocks_task("merge_pr", healthy)
+
+    return {
+        "success": healthy,
+        "healthy": healthy,
+        "namespace": ns,
+        "required_tool": tool,
+        "configured": configured,
+        "registered_tools_checked": registered_list is not None,
+        "required_tool_registered": registered,
+        "required_tool_callable": callable_live,
+        "probe_source": source,
+        "ide_namespace_proven": ide_namespace_proven,
+        "error_type": None if healthy else error_type,
+        "error_message": error_message or None,
+        "reasons": reasons,
+        "remediation": remediation,
+        "diagnostics": {
+            "namespace": ns,
+            "required_tool": tool,
+            "process_pid": process_pid,
+            "profile": profile_name,
+            "env": env_summary,
+            "config_path": config_path,
+            "probe_source": source,
+        },
+        "blocks_merge_workflow": blocks,
+    }
+
+
+def namespace_health_blocks_task(task: str, healthy: bool) -> bool:
+    """Return whether a broken namespace must block a workflow task."""
+    if healthy:
+        return False
+    return (task or "").strip() in {"merge_pr", "review_pr", "submit_review"}
+
+
+def required_namespace_for_task(task: str) -> str | None:
+    """Map a mutation task to the MCP namespace that must be healthy."""
+    return TASK_REQUIRED_NAMESPACES.get((task or "").strip())
+
+
+def mutation_gate_from_session(
+    task: str,
+    session_health: dict[str, dict[str, Any]] | None,
+) -> list[str]:
+    """Fail-closed gate using recorded client-namespace health assessments.
+
+    * Missing session entry → no gate (caller has not assessed yet).
+    * Client-namespace unhealthy / not IDE-proven → block mutation.
+    * Offline-only session entries never authorize mutations.
+    """
+    ns = required_namespace_for_task(task)
+    if not ns:
+        return []
+    store = session_health or {}
+    entry = store.get(ns)
+    if not entry:
+        return []
+    source = _normalize_probe_source(entry.get("probe_source"))
+    if source != PROBE_SOURCE_CLIENT:
+        return [
+            f"recorded namespace health for '{ns}' is probe_source={source}, "
+            "not client_namespace; re-probe through the IDE-managed path "
+            f"before {(task or 'mutation')}"
+        ]
+    if entry.get("ide_namespace_proven") and entry.get("healthy"):
+        return []
+    if entry.get("blocks_merge_workflow") or not entry.get("healthy"):
+        detail = entry.get("error_type") or "unhealthy"
+        return [
+            f"live MCP namespace '{ns}' is recorded {detail} "
+            f"(probe_source={source}); repair the IDE namespace before "
+            f"{(task or 'mutation')} (fail closed, #543)"
+        ]
+    if not entry.get("ide_namespace_proven"):
+        return [
+            f"live MCP namespace '{ns}' is not IDE-proven; supply a "
+            "client_namespace probe before mutation (fail closed, #543)"
+        ]
+    return []

mcp_server.py

@@ -6,6 +6,9 @@ Runs over stdio. All tools authenticate via macOS keychain (git credential fill)
 import os
 import sys
 
+sys.stderr = open("/tmp/mcp_server_stderr.log", "a", buffering=1)
+sys.stderr.write(f"\n--- MCP SERVER STARTUP (PID {os.getpid()}) ---\n")
+
 from role_session_router import (
     python_bytes_have_conflict_markers,
     skip_python_scan_walk_root,

mcp_session_state.py

@@ -30,6 +30,9 @@ DEFAULT_TTL_HOURS = 4.0
 
 KIND_WORKFLOW_LOAD = "review_workflow_load"
 KIND_DECISION_LOCK = "review_decision_lock"
+KIND_REVIEW_DRAFT = "review_draft"
+
+
 
 _SAFE_SEGMENT_RE = re.compile(r"[^A-Za-z0-9._+-]+")
 SESSION_PROFILE_LOCK_ENV = "GITEA_SESSION_PROFILE_LOCK"

review_merge_state_machine.py

@@ -93,8 +93,16 @@ def assess_workflow_blockers(
     capability_blocked: bool = False,
     mcp_reconnect_failed: bool = False,
     stale_capability_state: bool = False,
+    live_namespace_broken: bool = False,
 ) -> dict[str, Any]:
-    """Return hard blockers that forbid all PR queue work (#290 AC3)."""
+    """Return hard blockers that forbid all PR queue work (#290 AC3).
+
+    ``live_namespace_broken`` fails the merge/review path closed when the live
+    MCP namespace call path is unusable (e.g. ``client is closing: EOF``) even
+    though the tool is registered in FastMCP (#543 AC5). Feed it the
+    ``blocks_merge_workflow`` verdict from
+    ``mcp_namespace_health.classify_namespace_probe``.
+    """
     reasons: list[str] = []
     if infra_stop:
         reasons.append("infra_stop is active; PR selection/review/merge is forbidden")
@@ -104,6 +112,12 @@ def assess_workflow_blockers(
         reasons.append("MCP reconnect failed; stale session state cannot be reused")
     if stale_capability_state:
         reasons.append("stale MCP capability state detected after reconnect failure")
+    if live_namespace_broken:
+        reasons.append(
+            "live MCP namespace call path is broken (registered in FastMCP but "
+            "not callable through the namespace); repair the namespace before "
+            "review/merge"
+        )
     return {
         "block": bool(reasons),
         "reasons": reasons,
@@ -118,16 +132,19 @@ def assess_state_advancement(
     state_completion: dict[str, bool] | None,
     *,
     target_state: str,
-    infra_stop: bool = False,
-    capability_blocked: bool = False,
+    **blocker_kwargs,
 ) -> dict[str, Any]:
-    """Fail closed when *target_state* is requested before upstream gates pass."""
+    """Fail closed when *target_state* is requested before upstream gates pass.
+
+    Forwards every blocker flag (``infra_stop``, ``capability_blocked``,
+    ``mcp_reconnect_failed``, ``stale_capability_state``,
+    ``live_namespace_broken``) to :func:`assess_workflow_blockers` so
+    ``can_approve``/``can_merge`` honor the full blocker set, not just
+    infra_stop/capability_blocked (#543 AC5).
+    """
     completion = dict(state_completion or {})
     target = _clean(target_state).upper()
-    blockers = assess_workflow_blockers(
-        infra_stop=infra_stop,
-        capability_blocked=capability_blocked,
-    )
+    blockers = assess_workflow_blockers(**blocker_kwargs)
     reasons = list(blockers["reasons"])
 
     try:

stale_review_decision_lock.py

@@ -1,4 +1,4 @@
-"""Stale / moot #332 review-decision lock detection and cleanup policy (#594).
+"""Stale / moot #332 review-decision lock detection and cleanup policy (#594/#620).
 
 #332 correctly hard-stops a reviewer session after a terminal live review
 mutation. After #559 those locks are durable on disk, so they can outlive the
@@ -6,6 +6,12 @@ work they protect: when the referenced PR is already merged or closed, no
 same-PR merge sequence remains, yet the durable ledger still blocks unrelated
 new terminal reviews.
 
+#620 scopes the terminal boundary by **reviewed head SHA**: a prior
+REQUEST_CHANGES (or APPROVE) on head A must not block a fresh formal decision
+on head B of the **same open PR**. Same-head duplicates remain fail-closed.
+Open-PR lock *cleanup* remains forbidden unless the PR is truly merged/closed
+(#594); new-head re-review is allowed without deleting the durable lock.
+
 This module is pure policy (no Gitea I/O). The MCP tool
 ``gitea_cleanup_stale_review_decision_lock`` fetches live PR state, calls these
 helpers, and only then clears durable state when cleanup is allowed.
@@ -23,6 +29,45 @@ from typing import Any
 TERMINAL_REVIEW_ACTIONS = frozenset({"approve", "request_changes"})
 
 
+def normalize_head_sha(value: Any) -> str | None:
+    """Normalize a git SHA for equality comparison; None if empty/invalid."""
+    if value is None:
+        return None
+    text = str(value).strip().lower()
+    if not text:
+        return None
+    return text
+
+
+def heads_equal(a: Any, b: Any) -> bool:
+    na = normalize_head_sha(a)
+    nb = normalize_head_sha(b)
+    if not na or not nb:
+        return False
+    return na == nb
+
+
+def mutation_head_sha(mutation: dict | None, lock: dict | None = None) -> str | None:
+    """Head SHA that bounds a live mutation (#620).
+
+    Prefers fields recorded on the mutation itself. For *legacy* mutations
+    that predate head-scoping, falls back to the lock's
+    ``ready_expected_head_sha`` only when that ready binding is for the same
+    PR number (the frozen durable PR #619-style ledger).
+    """
+    if not isinstance(mutation, dict):
+        return None
+    for key in ("head_sha", "expected_head_sha", "reviewed_head_sha"):
+        head = normalize_head_sha(mutation.get(key))
+        if head:
+            return head
+    if not isinstance(lock, dict):
+        return None
+    if lock.get("ready_pr_number") != mutation.get("pr_number"):
+        return None
+    return normalize_head_sha(lock.get("ready_expected_head_sha"))
+
+
 def last_terminal_mutation(lock: dict | None) -> dict | None:
     """Return the last terminal live mutation on *lock*, or None."""
     if not lock:
@@ -35,18 +80,125 @@ def last_terminal_mutation(lock: dict | None) -> dict | None:
     return terminals[-1] if terminals else None
 
 
+def prior_live_mutations_block_boundary(
+    lock: dict | None,
+    *,
+    pr_number: int,
+    expected_head_sha: str | None,
+) -> bool:
+    """True when prior live mutations block a new decision for PR+head (#620).
+
+    Historical terminals on a **different head of the same PR** do not block.
+    Any prior mutation on another PR, the same head, or without a comparable
+    head SHA fails closed (blocks).
+
+    Head resolution uses ``mutation_head_sha(m, lock)`` so pre-#620 ledgers
+    that only stored ``ready_expected_head_sha`` still compare correctly
+    (PR #619-style).
+    """
+    if not lock:
+        return False
+    if lock.get("correction_authorized"):
+        return False
+    prior = list(lock.get("live_mutations") or [])
+    if not prior:
+        return False
+    target = normalize_head_sha(expected_head_sha)
+    for m in prior:
+        if not isinstance(m, dict):
+            return True
+        m_pr = m.get("pr_number")
+        m_head = mutation_head_sha(m, lock)
+        if (
+            m_pr == pr_number
+            and target
+            and m_head
+            and not heads_equal(m_head, target)
+        ):
+            # Same open PR, different reviewed head — historical boundary only.
+            continue
+        return True
+    return False
+
+
+def terminal_boundary_allows_fresh_decision(
+    lock: dict | None,
+    *,
+    pr_number: int,
+    expected_head_sha: str | None,
+    operation: str,
+) -> bool:
+    """Whether #332 hard-stop should yield for a new PR+head boundary (#620).
+
+    Only for ``mark_ready`` / ``review`` / ``resume`` on the **same PR** when
+    the requested head differs from the last terminal's head. Merge is never
+    reopened by head change (approved head merge path is separate).
+    """
+    if operation not in ("mark_ready", "review", "resume"):
+        return False
+    if not lock:
+        return False
+    if lock.get("correction_authorized"):
+        return True
+    last = last_terminal_mutation(lock)
+    if last is None:
+        return True
+    if last.get("pr_number") != pr_number:
+        return False
+    locked_head = mutation_head_sha(last, lock)
+    target = normalize_head_sha(expected_head_sha)
+    if not locked_head or not target:
+        return False
+    return not heads_equal(locked_head, target)
+
+
+def backfill_terminal_heads_from_ready(lock: dict) -> dict:
+    """Stamp head_sha onto legacy terminal mutations before overwriting ready_*.
+
+    Called when marking a fresh decision on a new head so historical rows keep
+    their original boundary after ``ready_expected_head_sha`` advances (#620).
+    """
+    if not isinstance(lock, dict):
+        return lock
+    ready_pr = lock.get("ready_pr_number")
+    ready_head = normalize_head_sha(lock.get("ready_expected_head_sha"))
+    if ready_pr is None or not ready_head:
+        return lock
+    mutations = list(lock.get("live_mutations") or [])
+    changed = False
+    for m in mutations:
+        if not isinstance(m, dict):
+            continue
+        if m.get("action") not in TERMINAL_REVIEW_ACTIONS:
+            continue
+        if m.get("pr_number") != ready_pr:
+            continue
+        if mutation_head_sha(m):
+            continue
+        m["head_sha"] = ready_head
+        changed = True
+    if changed:
+        lock["live_mutations"] = mutations
+    return lock
+
+
 def classify_pr_live_state(pr_live: dict | None) -> dict[str, Any]:
     """Normalize a Gitea PR payload into merge/closed flags."""
     pr = pr_live or {}
     merged = bool(pr.get("merged") or pr.get("merged_at"))
     state = (pr.get("state") or "").strip().lower() or None
     closed = state == "closed"
+    head = pr.get("head") if isinstance(pr.get("head"), dict) else {}
+    head_sha = normalize_head_sha(
+        pr.get("head_sha") or pr.get("head_commit_sha") or head.get("sha")
+    )
     return {
         "pr_state": state,
         "pr_merged": merged,
         "pr_merged_or_closed": merged or closed,
         "merge_commit_sha": pr.get("merge_commit_sha")
         or pr.get("merged_commit_sha"),
+        "current_pr_head_sha": head_sha,
     }
 
 
@@ -56,6 +208,7 @@ def lock_summary(lock: dict | None) -> dict[str, Any] | None:
         return None
     last = last_terminal_mutation(lock)
     mutations = list(lock.get("live_mutations") or [])
+    last_head = mutation_head_sha(last, lock) if last else None
     return {
         "task": lock.get("task"),
         "remote": lock.get("remote"),
@@ -67,16 +220,21 @@ def lock_summary(lock: dict | None) -> dict[str, Any] | None:
         "session_profile": lock.get("session_profile"),
         "ready_pr_number": lock.get("ready_pr_number"),
         "ready_action": lock.get("ready_action"),
+        "ready_expected_head_sha": normalize_head_sha(
+            lock.get("ready_expected_head_sha")
+        ),
         "live_mutations_count": len(mutations),
         "last_terminal": (
             {
                 "pr_number": last.get("pr_number"),
                 "action": last.get("action"),
                 "review_id": last.get("review_id"),
+                "head_sha": last_head,
             }
             if last
             else None
         ),
+        "locked_head_sha": last_head,
         "correction_authorized": bool(lock.get("correction_authorized")),
         "updated_at": lock.get("updated_at") or lock.get("recorded_at"),
     }
@@ -88,13 +246,16 @@ def assess_stale_review_decision_lock(
     pr_live: dict | None = None,
     pr_lookup_error: str | None = None,
     active_profile_identity: str | None = None,
+    current_pr_head_sha: str | None = None,
 ) -> dict[str, Any]:
-    """Assess whether a durable review-decision lock is stale/moot (#594).
+    """Assess whether a durable review-decision lock is stale/moot (#594/#620).
 
     *pr_live* must be the live Gitea payload for the **last terminal
     mutation's PR**. When no lock / no terminal mutation exists, cleanup is
     not applicable. When the PR is still open (or lookup fails), cleanup is
-    forbidden and #332 hard-stop remains in force.
+    forbidden (#594). Open PR + different live head reports
+    ``stale_by_head`` / ``fresh_review_on_current_head_allowed`` (#620)
+    without enabling cleanup.
     """
     summary = lock_summary(lock)
     result: dict[str, Any] = {
@@ -102,6 +263,10 @@ def assess_stale_review_decision_lock(
         "lock_summary": summary,
         "last_terminal_pr": None,
         "last_terminal_action": None,
+        "locked_head_sha": None,
+        "current_pr_head_sha": normalize_head_sha(current_pr_head_sha),
+        "stale_by_head": False,
+        "fresh_review_on_current_head_allowed": False,
         "is_moot": False,
         "cleanup_allowed": False,
         "profile_match": True,
@@ -141,8 +306,10 @@ def assess_stale_review_decision_lock(
 
     pr_number = last.get("pr_number")
     action = last.get("action")
+    locked_head = mutation_head_sha(last, lock)
     result["last_terminal_pr"] = pr_number
     result["last_terminal_action"] = action
+    result["locked_head_sha"] = locked_head
 
     if pr_number is None:
         result["reasons"].append(
@@ -165,25 +332,46 @@ def assess_stale_review_decision_lock(
         return result
 
     live = classify_pr_live_state(pr_live)
+    current_head = normalize_head_sha(
+        current_pr_head_sha or live.get("current_pr_head_sha")
+    )
     result.update(
         {
             "pr_state": live["pr_state"],
             "pr_merged": live["pr_merged"],
             "pr_merged_or_closed": live["pr_merged_or_closed"],
             "merge_commit_sha": live["merge_commit_sha"],
+            "current_pr_head_sha": current_head,
         }
     )
 
     if not live["pr_merged_or_closed"]:
-        result["reasons"].append(
-            f"terminal review mutation on open PR #{pr_number} is still active "
-            f"({action}); #332 hard-stop remains — cleanup forbidden (#594)"
+        stale_by_head = bool(
+            locked_head and current_head and not heads_equal(locked_head, current_head)
         )
+        result["stale_by_head"] = stale_by_head
+        # Fresh formal decision is allowed on the new head without cleanup (#620).
+        result["fresh_review_on_current_head_allowed"] = stale_by_head
+        if stale_by_head:
+            result["reasons"].append(
+                f"terminal {action} on PR #{pr_number} is bound to head "
+                f"{locked_head[:12]}…; live head is {current_head[:12]}… — "
+                "fresh formal review on current head is allowed without "
+                "cleanup (fail closed for cleanup, #620); #332 same-head "
+                "duplicate protection remains"
+            )
+        else:
+            result["reasons"].append(
+                f"terminal review mutation on open PR #{pr_number} is still active "
+                f"({action}); #332 hard-stop remains — cleanup forbidden (#594)"
+            )
         return result
 
     # Merged or closed: lock is moot. Same-PR merge continuation is impossible.
     result["is_moot"] = True
     result["cleanup_allowed"] = True
+    result["stale_by_head"] = False
+    result["fresh_review_on_current_head_allowed"] = False
     result["reasons"].append(
         f"terminal mutation ({action} on PR #{pr_number}) is moot: PR is "
         f"{'merged' if live['pr_merged'] else 'closed'}; canonical cleanup allowed (#594)"

test_mcp_conn.py

@@ -1,20 +1,45 @@
 #!/usr/bin/env python3
-"""Live health-check script to verify Gitea MCP namespace connections.
+"""Offline-only MCP namespace spawn probe (NOT IDE-namespace proof).
 
-Spawns the MCP server processes as defined in the IDE's global config,
-performs the JSON-RPC handshake, and queries the tools list to verify
-that the connection is fully operational and doesn't return EOF.
+Spawns a *separate* MCP server process from config via subprocess.Popen,
+performs the JSON-RPC handshake, verifies the required tool is registered,
+and invokes that tool. Results are classified with
+``probe_source=offline_spawn``.
+
+This path is useful for offline launch/registration debugging. It does
+**not** prove the IDE-managed MCP client namespace is healthy (#543). For
+workflow gates, pass live IDE call evidence with
+``probe_source=client_namespace`` to ``gitea_assess_mcp_namespace_health``.
 """
+
+import argparse
 import json
 import os
 import subprocess
 import sys
 
-def run_connection_test(name, config):
+from mcp_namespace_health import REQUIRED_NAMESPACE_TOOLS, classify_namespace_probe
+
+
+def _read_json_line(proc):
+    line = proc.stdout.readline()
+    if not line:
+        stderr_content = proc.stderr.read()
+        return None, stderr_content
+    return json.loads(line), None
+
+
+def _write_message(proc, payload):
+    proc.stdin.write(json.dumps(payload) + "\n")
+    proc.stdin.flush()
+
+
+def run_connection_test(name, config, *, required_tool=None, config_path=None):
     print(f"Testing MCP connection for '{name}'...")
     command = config.get("command")
     args = config.get("args", [])
     env = config.get("env", {})
+    tool_name = required_tool or REQUIRED_NAMESPACE_TOOLS.get(name) or "gitea_whoami"
     
     # Merge current environment
     run_env = os.environ.copy()
@@ -31,8 +56,17 @@ def run_connection_test(name, config):
             bufsize=1,
             env=run_env
         )
-    except Exception as e:
-        print(f"  [FAIL] Failed to spawn process: {e}")
+    except Exception as exc:
+        print(f"  [FAIL] Failed to spawn process: {exc}")
+        assessment = classify_namespace_probe(
+            name,
+            required_tool=tool_name,
+            probe_result={"success": False, "error": str(exc)},
+            process={"profile": env.get("GITEA_MCP_PROFILE"), "env": env},
+            config_path=config_path,
+                probe_source="offline_spawn",
+        )
+        print(f"  diagnostics: {json.dumps(assessment['diagnostics'], sort_keys=True)}")
         return False
 
     # Send initialize request
@@ -48,26 +82,36 @@ def run_connection_test(name, config):
     }
     
     try:
-        proc.stdin.write(json.dumps(init_req) + "\n")
-        proc.stdin.flush()
+        _write_message(proc, init_req)
         
         # Read response
-        line = proc.stdout.readline()
-        if not line:
-            stderr_content = proc.stderr.read()
+        res, stderr_content = _read_json_line(proc)
+        if res is None:
             print(f"  [FAIL] Received EOF from process. Stderr:\n{stderr_content}")
+            assessment = classify_namespace_probe(
+                name,
+                required_tool=tool_name,
+                probe_result={"success": False, "error": stderr_content or "EOF"},
+                process={
+                    "pid": proc.pid,
+                    "profile": env.get("GITEA_MCP_PROFILE"),
+                    "env": env,
+                },
+                config_path=config_path,
+                probe_source="offline_spawn",
+            )
+            print(f"  remediation: {' '.join(assessment['remediation'])}")
             proc.terminate()
             return False
             
-        print(f"  [OK] Received initialize response: {line.strip()[:150]}...")
+        print(f"  [OK] Received initialize response: {str(res)[:150]}...")
         
         # Send initialized notification
         init_notif = {
             "jsonrpc": "2.0",
             "method": "notifications/initialized"
         }
-        proc.stdin.write(json.dumps(init_notif) + "\n")
-        proc.stdin.flush()
+        _write_message(proc, init_notif)
         
         # Send tools/list request
         list_req = {
@@ -76,16 +120,27 @@ def run_connection_test(name, config):
             "params": {},
             "id": 2
         }
-        proc.stdin.write(json.dumps(list_req) + "\n")
-        proc.stdin.flush()
+        _write_message(proc, list_req)
         
-        line = proc.stdout.readline()
-        if not line:
+        res, stderr_content = _read_json_line(proc)
+        if res is None:
             print("  [FAIL] Received EOF on tools/list request.")
+            assessment = classify_namespace_probe(
+                name,
+                required_tool=tool_name,
+                probe_result={"success": False, "error": stderr_content or "EOF"},
+                process={
+                    "pid": proc.pid,
+                    "profile": env.get("GITEA_MCP_PROFILE"),
+                    "env": env,
+                },
+                config_path=config_path,
+                probe_source="offline_spawn",
+            )
+            print(f"  remediation: {' '.join(assessment['remediation'])}")
             proc.terminate()
             return False
             
-        res = json.loads(line)
         if "error" in res:
             print(f"  [FAIL] Server returned error: {res['error']}")
             proc.terminate()
@@ -94,16 +149,115 @@ def run_connection_test(name, config):
         tools = res.get("result", {}).get("tools", [])
         tool_names = [t.get("name") for t in tools]
         print(f"  [OK] Successfully retrieved {len(tool_names)} tools: {tool_names[:5]}...")
+        if tool_name not in tool_names:
+            assessment = classify_namespace_probe(
+                name,
+                required_tool=tool_name,
+                registered_tools=tool_names,
+                probe_result={"success": False, "error": "required tool missing"},
+                process={
+                    "pid": proc.pid,
+                    "profile": env.get("GITEA_MCP_PROFILE"),
+                    "env": env,
+                },
+                config_path=config_path,
+                probe_source="offline_spawn",
+            )
+            print(f"  [FAIL] Required tool '{tool_name}' is not registered.")
+            print(f"  remediation: {' '.join(assessment['remediation'])}")
+            proc.terminate()
+            return False
+
+        call_req = {
+            "jsonrpc": "2.0",
+            "method": "tools/call",
+            "params": {"name": tool_name, "arguments": {}},
+            "id": 3,
+        }
+        _write_message(proc, call_req)
+
+        call_res, stderr_content = _read_json_line(proc)
+        if call_res is None:
+            assessment = classify_namespace_probe(
+                name,
+                required_tool=tool_name,
+                registered_tools=tool_names,
+                probe_result={"success": False, "error": stderr_content or "EOF"},
+                process={
+                    "pid": proc.pid,
+                    "profile": env.get("GITEA_MCP_PROFILE"),
+                    "env": env,
+                },
+                config_path=config_path,
+                probe_source="offline_spawn",
+            )
+            print(f"  [FAIL] Received EOF on {tool_name} invocation.")
+            print(f"  diagnostics: {json.dumps(assessment['diagnostics'], sort_keys=True)}")
+            print(f"  remediation: {' '.join(assessment['remediation'])}")
+            proc.terminate()
+            return False
+        if "error" in call_res:
+            assessment = classify_namespace_probe(
+                name,
+                required_tool=tool_name,
+                registered_tools=tool_names,
+                probe_result={"success": False, "error": call_res["error"]},
+                process={
+                    "pid": proc.pid,
+                    "profile": env.get("GITEA_MCP_PROFILE"),
+                    "env": env,
+                },
+                config_path=config_path,
+                probe_source="offline_spawn",
+            )
+            print(f"  [FAIL] {tool_name} invocation returned error: {call_res['error']}")
+            print(f"  remediation: {' '.join(assessment['remediation'])}")
+            proc.terminate()
+            return False
+
+        assessment = classify_namespace_probe(
+            name,
+            required_tool=tool_name,
+            registered_tools=tool_names,
+            probe_result={"success": True, "result": call_res.get("result")},
+            process={
+                "pid": proc.pid,
+                "profile": env.get("GITEA_MCP_PROFILE"),
+                "env": env,
+            },
+            config_path=config_path,
+                probe_source="offline_spawn",
+        )
+        print(f"  [OK] Successfully invoked required tool '{tool_name}'.")
+        print(f"  diagnostics: {json.dumps(assessment['diagnostics'], sort_keys=True)}")
         
         proc.terminate()
         return True
-    except Exception as e:
-        print(f"  [FAIL] Error during handshake: {e}")
+    except Exception as exc:
+        print(f"  [FAIL] Error during handshake: {exc}")
         proc.terminate()
         return False
 
+
 def main():
-    config_path = "/Users/jasonwalker/.gemini/config/mcp_config.json"
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--config",
+        default=os.environ.get(
+            "MCP_CONFIG_PATH",
+            os.path.expanduser("~/.gemini/config/mcp_config.json"),
+        ),
+        help="Path to MCP config JSON.",
+    )
+    parser.add_argument(
+        "--namespace",
+        action="append",
+        dest="namespaces",
+        help="Namespace to test. May be repeated.",
+    )
+    args = parser.parse_args()
+
+    config_path = args.config
     try:
         with open(config_path) as f:
             mcp_config = json.load(f)
@@ -112,10 +266,16 @@ def main():
         sys.exit(1)
         
     servers = mcp_config.get("mcpServers", {})
+    namespaces = args.namespaces or list(REQUIRED_NAMESPACE_TOOLS)
     failed = False
-    for name in ["gitea-author", "gitea-reviewer"]:
+    for name in namespaces:
         if name in servers:
-            if not run_connection_test(name, servers[name]):
+            if not run_connection_test(
+                name,
+                servers[name],
+                required_tool=REQUIRED_NAMESPACE_TOOLS.get(name),
+                config_path=config_path,
+            ):
                 failed = True
         else:
             print(f"Server '{name}' not found in mcp_config.json")

tests/conftest.py

@@ -66,6 +66,7 @@ def _reset_mutation_authority(monkeypatch):
     monkeypatch.setattr(mcp_server, "_MUTATION_AUTHORITY", None)
     monkeypatch.setattr(mcp_server, "_IDENTITY_CACHE", {})
     monkeypatch.setattr(mcp_server, "_REVIEW_DECISION_LOCK", None)
+    monkeypatch.setattr(mcp_server, "_LIVE_NAMESPACE_HEALTH", {})
     monkeypatch.setattr(mcp_server, "_preflight_whoami_called", False)
     monkeypatch.setattr(mcp_server, "_preflight_capability_called", False)
     monkeypatch.setattr(mcp_server, "_preflight_resolved_role", None)

tests/test_head_scoped_review_decision_lock.py

@@ -0,0 +1,397 @@
+"""Head-scoped #332 review-decision locks (#620).
+
+Proves:
+  * REQUEST_CHANGES on head A does not block mark_ready/submit on head B
+  * APPROVE on head B is allowed after RC on head A (same open PR)
+  * same-head duplicate terminal remains blocked
+  * open-PR cleanup remains forbidden; assessment reports stale_by_head
+  * historical mutations keep their head_sha (preserved ledger)
+  * PR #619-style: old RC at 036b78e…, current head 2429d9d…, approve allowed
+"""
+
+from __future__ import annotations
+
+import os
+import unittest
+from unittest.mock import patch
+
+import mcp_server
+import stale_review_decision_lock as srdl
+
+HEAD_A = "036b78e31ea5d036452b3a52e0e086b01e0c763f"
+HEAD_B = "2429d9d2e826e519eb8eb4ade45987c00838aefb"
+HEAD_C = "c" * 40
+
+
+def _lock(mutations=None, correction=False, ready_pr=None, ready_head=None, ready_action=None):
+    return {
+        "task": "review_pr",
+        "remote": "prgs",
+        "org": "Scaled-Tech-Consulting",
+        "repo": "Gitea-Tools",
+        "session_pid": os.getpid(),
+        "session_profile": "prgs-reviewer",
+        "session_profile_lock": "prgs-reviewer",
+        "profile_identity": "prgs-reviewer",
+        "final_review_decision_ready": False,
+        "ready_pr_number": ready_pr,
+        "ready_action": ready_action,
+        "ready_expected_head_sha": ready_head,
+        "ready_remote": "prgs" if ready_pr else None,
+        "ready_org": "Scaled-Tech-Consulting" if ready_pr else None,
+        "ready_repo": "Gitea-Tools" if ready_pr else None,
+        "live_mutations": list(mutations or []),
+        "correction_authorized": correction,
+        "correction_reason": None,
+    }
+
+
+RC_619_LEGACY = {
+    "pr_number": 619,
+    "action": "request_changes",
+    "review_id": 410,
+    "review_state": "request_changes",
+    # no head_sha — pre-#620 durable ledger shape
+}
+RC_619_HEAD_A = {
+    "pr_number": 619,
+    "action": "request_changes",
+    "review_id": 410,
+    "review_state": "request_changes",
+    "head_sha": HEAD_A,
+}
+APPROVE_619_HEAD_B = {
+    "pr_number": 619,
+    "action": "approve",
+    "review_id": 411,
+    "review_state": "approve",
+    "head_sha": HEAD_B,
+}
+
+
+def _seed(mutations=None, **kwargs):
+    import review_workflow_load
+
+    review_workflow_load.record_review_workflow_load(mcp_server.PROJECT_ROOT)
+    mcp_server._save_review_decision_lock(_lock(mutations, **kwargs))
+    mcp_server.gitea_load_review_workflow()
+
+
+def _open_pr(pr_number=619, head=HEAD_B):
+    return {
+        "number": pr_number,
+        "state": "open",
+        "merged": False,
+        "merged_at": None,
+        "head": {"sha": head},
+    }
+
+
+def _no_lease():
+    return {"block": False, "reasons": [], "mutation_allowed": True}
+
+
+def _feedback(blocking=False, stale=False, success=True):
+    return {
+        "success": success,
+        "has_blocking_change_requests": blocking,
+        "review_feedback_stale": stale,
+        "current_head_sha": HEAD_B,
+    }
+
+
+class TestPureHeadScopeHelpers(unittest.TestCase):
+    def test_mutation_head_prefers_recorded_sha(self):
+        m = {"pr_number": 1, "head_sha": HEAD_A}
+        self.assertEqual(srdl.mutation_head_sha(m), HEAD_A)
+
+    def test_legacy_mutation_uses_ready_expected_for_same_pr(self):
+        lock = _lock(
+            [RC_619_LEGACY],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        self.assertEqual(srdl.mutation_head_sha(RC_619_LEGACY, lock), HEAD_A)
+
+    def test_legacy_mutation_ignores_ready_for_other_pr(self):
+        lock = _lock([RC_619_LEGACY], ready_pr=1, ready_head=HEAD_A)
+        self.assertIsNone(srdl.mutation_head_sha(RC_619_LEGACY, lock))
+
+    def test_prior_blocks_same_head_not_other_head(self):
+        lock = _lock([RC_619_HEAD_A])
+        self.assertTrue(
+            srdl.prior_live_mutations_block_boundary(
+                lock, pr_number=619, expected_head_sha=HEAD_A
+            )
+        )
+        self.assertFalse(
+            srdl.prior_live_mutations_block_boundary(
+                lock, pr_number=619, expected_head_sha=HEAD_B
+            )
+        )
+
+    def test_backfill_stamps_legacy_terminals(self):
+        lock = _lock(
+            [dict(RC_619_LEGACY)],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        srdl.backfill_terminal_heads_from_ready(lock)
+        self.assertEqual(lock["live_mutations"][0]["head_sha"], HEAD_A)
+
+
+class TestHardStopHeadScope(unittest.TestCase):
+    def tearDown(self):
+        mcp_server._save_review_decision_lock(None)
+        mcp_server.review_workflow_load.clear_review_workflow_load()
+
+    def test_rc_head_a_allows_mark_ready_head_b(self):
+        _seed(
+            [RC_619_HEAD_A],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        self.assertEqual(
+            mcp_server.terminal_review_hard_stop_reasons(
+                619, "mark_ready", expected_head_sha=HEAD_B
+            ),
+            [],
+        )
+
+    def test_rc_head_a_blocks_mark_ready_same_head(self):
+        _seed(
+            [RC_619_HEAD_A],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        reasons = mcp_server.terminal_review_hard_stop_reasons(
+            619, "mark_ready", expected_head_sha=HEAD_A
+        )
+        self.assertTrue(reasons)
+        self.assertIn("#332", reasons[0])
+
+    def test_rc_head_a_blocks_other_pr(self):
+        _seed([RC_619_HEAD_A], ready_pr=619, ready_head=HEAD_A)
+        reasons = mcp_server.terminal_review_hard_stop_reasons(
+            700, "mark_ready", expected_head_sha=HEAD_B
+        )
+        self.assertTrue(reasons)
+
+    def test_legacy_619_ledger_allows_new_head(self):
+        """PR #619-style durable lock without mutation head_sha."""
+        _seed(
+            [RC_619_LEGACY],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        self.assertEqual(
+            mcp_server.terminal_review_hard_stop_reasons(
+                619, "mark_ready", expected_head_sha=HEAD_B
+            ),
+            [],
+        )
+
+
+class TestMarkFinalAndRecord(unittest.TestCase):
+    def tearDown(self):
+        mcp_server._save_review_decision_lock(None)
+        mcp_server.review_workflow_load.clear_review_workflow_load()
+
+    def _mark(self, pr, action, head, feedback=None):
+        with patch("mcp_server._list_pr_lease_comments", return_value=[]), patch(
+            "mcp_server._pr_work_lease_reviewer_block", return_value=_no_lease()
+        ), patch.object(
+            mcp_server,
+            "gitea_get_pr_review_feedback",
+            return_value=feedback or _feedback(blocking=False, stale=True),
+        ), patch.object(
+            mcp_server,
+            "gitea_check_pr_eligibility",
+            return_value={"eligible": True, "head_sha": head},
+        ):
+            return mcp_server.gitea_mark_final_review_decision(
+                pr_number=pr,
+                action=action,
+                expected_head_sha=head,
+                remote="prgs",
+                org="Scaled-Tech-Consulting",
+                repo="Gitea-Tools",
+            )
+
+    def test_rc_then_rc_on_new_head(self):
+        _seed(
+            [RC_619_HEAD_A],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        # Prior RC at head A is unresolved but head moved → feedback stale.
+        res = self._mark(
+            619,
+            "request_changes",
+            HEAD_B,
+            feedback=_feedback(blocking=True, stale=True),
+        )
+        self.assertTrue(res.get("marked_ready"), res)
+        lock = mcp_server._load_review_decision_lock()
+        # Historical head A preserved on mutation after backfill.
+        heads = {
+            m.get("head_sha")
+            for m in lock["live_mutations"]
+            if m.get("action") == "request_changes"
+        }
+        self.assertIn(HEAD_A, heads)
+        self.assertEqual(lock["ready_expected_head_sha"], HEAD_B)
+
+    def test_rc_then_approve_on_new_head(self):
+        _seed(
+            [RC_619_HEAD_A],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        res = self._mark(619, "approve", HEAD_B)
+        self.assertTrue(res.get("marked_ready"), res)
+        self.assertTrue(res.get("head_scoped"))
+
+    def test_same_head_rc_still_blocked_by_hard_stop(self):
+        _seed(
+            [RC_619_HEAD_A],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        res = self._mark(619, "approve", HEAD_A)
+        self.assertFalse(res.get("marked_ready"))
+        self.assertTrue(any("#332" in r for r in res.get("reasons") or []))
+
+    def test_pr619_style_legacy_lock_approve_on_current_head(self):
+        _seed(
+            [RC_619_LEGACY],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        res = self._mark(619, "approve", HEAD_B)
+        self.assertTrue(res.get("marked_ready"), res)
+        lock = mcp_server._load_review_decision_lock()
+        # Backfill should have stamped HEAD_A onto the legacy mutation.
+        self.assertEqual(lock["live_mutations"][0].get("head_sha"), HEAD_A)
+        self.assertEqual(lock["ready_expected_head_sha"], HEAD_B)
+
+    def test_record_live_mutation_stores_head(self):
+        _seed(ready_pr=619, ready_head=HEAD_B, ready_action="approve")
+        lock = mcp_server._load_review_decision_lock()
+        lock["final_review_decision_ready"] = True
+        lock["ready_pr_number"] = 619
+        lock["ready_expected_head_sha"] = HEAD_B
+        mcp_server._save_review_decision_lock(lock)
+        mcp_server.record_live_review_mutation(619, "approve", review_id=99)
+        stored = mcp_server._load_review_decision_lock()["live_mutations"][-1]
+        self.assertEqual(stored["head_sha"], HEAD_B)
+        self.assertEqual(stored["pr_number"], 619)
+
+    def test_submit_gate_allows_new_head_after_prior_terminal(self):
+        """check_review_decision_gate must not block different-head submit."""
+        mutations = [RC_619_HEAD_A]
+        _seed(
+            mutations,
+            ready_pr=619,
+            ready_head=HEAD_B,
+            ready_action="approve",
+        )
+        lock = mcp_server._load_review_decision_lock()
+        lock["final_review_decision_ready"] = True
+        lock["ready_pr_number"] = 619
+        lock["ready_action"] = "approve"
+        lock["ready_expected_head_sha"] = HEAD_B
+        lock["ready_remote"] = "prgs"
+        lock["ready_org"] = "Scaled-Tech-Consulting"
+        lock["ready_repo"] = "Gitea-Tools"
+        mcp_server._save_review_decision_lock(lock)
+        reasons = mcp_server.check_review_decision_gate(
+            619,
+            "approve",
+            final_review_decision_ready=True,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+        )
+        self.assertEqual(reasons, [], reasons)
+
+    def test_submit_gate_blocks_same_head_duplicate(self):
+        mutations = [RC_619_HEAD_A]
+        _seed(
+            mutations,
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        lock = mcp_server._load_review_decision_lock()
+        lock["final_review_decision_ready"] = True
+        lock["ready_pr_number"] = 619
+        lock["ready_action"] = "request_changes"
+        lock["ready_expected_head_sha"] = HEAD_A
+        lock["ready_remote"] = "prgs"
+        lock["ready_org"] = "Scaled-Tech-Consulting"
+        lock["ready_repo"] = "Gitea-Tools"
+        mcp_server._save_review_decision_lock(lock)
+        reasons = mcp_server.check_review_decision_gate(
+            619,
+            "request_changes",
+            final_review_decision_ready=True,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+        )
+        self.assertTrue(reasons)
+
+
+class TestAssessmentOpenPrHead(unittest.TestCase):
+    def test_open_pr_stale_by_head_no_cleanup(self):
+        lock = _lock(
+            [RC_619_HEAD_A],
+            ready_pr=619,
+            ready_head=HEAD_A,
+            ready_action="request_changes",
+        )
+        a = srdl.assess_stale_review_decision_lock(
+            lock, pr_live=_open_pr(619, HEAD_B)
+        )
+        self.assertTrue(a["has_lock"])
+        self.assertFalse(a["is_moot"])
+        self.assertFalse(a["cleanup_allowed"])
+        self.assertTrue(a["stale_by_head"])
+        self.assertTrue(a["fresh_review_on_current_head_allowed"])
+        self.assertEqual(a["locked_head_sha"], HEAD_A)
+        self.assertEqual(a["current_pr_head_sha"], HEAD_B)
+
+    def test_open_pr_same_head_no_fresh(self):
+        lock = _lock([RC_619_HEAD_A], ready_pr=619, ready_head=HEAD_A)
+        a = srdl.assess_stale_review_decision_lock(
+            lock, pr_live=_open_pr(619, HEAD_A)
+        )
+        self.assertFalse(a["stale_by_head"])
+        self.assertFalse(a["fresh_review_on_current_head_allowed"])
+        self.assertFalse(a["cleanup_allowed"])
+
+    def test_historical_mutation_preserved_in_summary(self):
+        lock = _lock(
+            [RC_619_HEAD_A, APPROVE_619_HEAD_B],
+            ready_pr=619,
+            ready_head=HEAD_B,
+            ready_action="approve",
+        )
+        summary = srdl.lock_summary(lock)
+        self.assertEqual(summary["live_mutations_count"], 2)
+        self.assertEqual(summary["last_terminal"]["head_sha"], HEAD_B)
+        self.assertEqual(summary["locked_head_sha"], HEAD_B)
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_mcp_namespace_health.py

@@ -0,0 +1,208 @@
+import unittest
+
+import gitea_mcp_server
+import mcp_namespace_health
+import review_merge_state_machine as rmsm
+
+
+class TestMcpNamespaceHealth(unittest.TestCase):
+    def setUp(self):
+        gitea_mcp_server._LIVE_NAMESPACE_HEALTH.clear()
+
+    def test_registered_tool_but_live_eof_blocks_merge(self):
+        result = mcp_namespace_health.classify_namespace_probe(
+            "gitea-reviewer",
+            required_tool="gitea_whoami",
+            registered_tools=["gitea_whoami", "gitea_list_profiles"],
+            probe_result={
+                "success": False,
+                "error": "client is closing: EOF",
+            },
+            process={
+                "pid": 4321,
+                "profile": "prgs-reviewer",
+                "env": {
+                    "GITEA_MCP_PROFILE": "prgs-reviewer",
+                    "GITEA_TOKEN": "must-not-leak",
+                },
+            },
+            config_path="/Users/jasonwalker/.gemini/config/mcp_config.json",
+            probe_source="client_namespace",
+        )
+
+        self.assertFalse(result["healthy"])
+        self.assertEqual(result["error_type"], "namespace_eof")
+        self.assertTrue(result["required_tool_registered"])
+        self.assertFalse(result["required_tool_callable"])
+        self.assertTrue(result["blocks_merge_workflow"])
+        self.assertFalse(result["ide_namespace_proven"])
+        self.assertEqual(result["probe_source"], "client_namespace")
+        self.assertEqual(result["diagnostics"]["process_pid"], 4321)
+        self.assertEqual(result["diagnostics"]["profile"], "prgs-reviewer")
+        self.assertEqual(
+            result["diagnostics"]["env"]["GITEA_MCP_PROFILE"],
+            "prgs-reviewer",
+        )
+        self.assertNotIn("GITEA_TOKEN", result["diagnostics"]["env"])
+        self.assertIn("gitea-reviewer", result["reasons"][0])
+        self.assertIn("gitea_whoami", result["reasons"][0])
+
+    def test_successful_client_namespace_invocation_is_ide_proven(self):
+        result = mcp_namespace_health.classify_namespace_probe(
+            "gitea-author",
+            registered_tools=["gitea_whoami"],
+            probe_result={"success": True, "result": {"authenticated": True}},
+            process={"pid": 1234, "profile": "prgs-author"},
+            config_path="/tmp/mcp_config.json",
+            probe_source="client_namespace",
+        )
+
+        self.assertTrue(result["healthy"])
+        self.assertTrue(result["required_tool_registered"])
+        self.assertTrue(result["required_tool_callable"])
+        self.assertTrue(result["ide_namespace_proven"])
+        self.assertFalse(result["blocks_merge_workflow"])
+        self.assertIsNone(result["error_type"])
+
+    def test_offline_spawn_success_is_not_ide_proof(self):
+        result = mcp_namespace_health.classify_namespace_probe(
+            "gitea-merger",
+            registered_tools=["gitea_whoami"],
+            probe_result={"success": True, "result": {}},
+            process={"pid": 99, "profile": "prgs-merger"},
+            probe_source="offline_spawn",
+        )
+        self.assertTrue(result["healthy"])
+        self.assertFalse(result["ide_namespace_proven"])
+        self.assertFalse(result["blocks_merge_workflow"])
+        self.assertTrue(
+            any("offline_spawn" in r for r in result["reasons"])
+        )
+
+    def test_registered_missing_required_tool_fails_before_probe_success(self):
+        result = mcp_namespace_health.classify_namespace_probe(
+            "gitea-tools",
+            registered_tools=["gitea_whoami"],
+            probe_result={"success": True, "result": {}},
+            probe_source="client_namespace",
+        )
+
+        self.assertFalse(result["healthy"])
+        self.assertEqual(result["required_tool"], "gitea_list_profiles")
+        self.assertFalse(result["required_tool_registered"])
+        self.assertEqual(result["error_type"], "tool_missing")
+
+    def test_server_tool_exposes_same_assessment_and_records_session(self):
+        result = gitea_mcp_server.gitea_assess_mcp_namespace_health(
+            "gitea-merger",
+            registered_tools=["gitea_whoami"],
+            probe_result={"success": False, "error": "transport closed"},
+            process={"pid": 9876, "profile": "prgs-merger"},
+            probe_source="client_namespace",
+        )
+
+        self.assertFalse(result["success"])
+        self.assertEqual(result["error_type"], "namespace_eof")
+        self.assertEqual(result["namespace"], "gitea-merger")
+        self.assertEqual(result["diagnostics"]["process_pid"], 9876)
+        self.assertIn("gitea-merger", gitea_mcp_server._LIVE_NAMESPACE_HEALTH)
+        gate = gitea_mcp_server._live_namespace_health_gate("merge_pr")
+        self.assertTrue(gate)
+        self.assertTrue(any("gitea-merger" in r for r in gate))
+
+
+class TestLiveNamespaceBlocksMerge(unittest.TestCase):
+    """AC5: a broken live namespace must hard-block the review/merge state machine."""
+
+    def setUp(self):
+        gitea_mcp_server._LIVE_NAMESPACE_HEALTH.clear()
+
+    def _merge_ready_completion(self):
+        # Completion through PRE_MERGE_RECHECK is the state where a clean merge
+        # is otherwise allowed (see test_merge_allowed_with_pre_merge_gates).
+        idx = rmsm.REVIEW_MERGE_STATES.index("PRE_MERGE_RECHECK")
+        return {state: True for state in rmsm.REVIEW_MERGE_STATES[: idx + 1]}
+
+    def _all_gates(self):
+        return {gate: True for gate in rmsm._PRE_MERGE_REQUIRED_GATES}
+
+    def test_assess_workflow_blockers_flags_live_namespace_broken(self):
+        clean = rmsm.assess_workflow_blockers()
+        self.assertFalse(clean["block"])
+
+        broken = rmsm.assess_workflow_blockers(live_namespace_broken=True)
+        self.assertTrue(broken["block"])
+        self.assertTrue(any("namespace" in r.lower() for r in broken["reasons"]))
+
+    def test_can_merge_blocks_even_when_all_gates_pass(self):
+        # Without the namespace blocker a fully-complete workflow can merge...
+        allowed = rmsm.can_merge(
+            self._merge_ready_completion(), pre_merge_gates=self._all_gates()
+        )
+        self.assertTrue(allowed["allowed"])
+
+        # ...but a broken live namespace overrides every satisfied gate.
+        blocked = rmsm.can_merge(
+            self._merge_ready_completion(),
+            pre_merge_gates=self._all_gates(),
+            live_namespace_broken=True,
+        )
+        self.assertTrue(blocked["block"])
+        self.assertFalse(blocked["allowed"])
+
+    def test_workflow_status_forwards_namespace_blocker(self):
+        status = rmsm.workflow_status(
+            self._merge_ready_completion(), live_namespace_broken=True
+        )
+        self.assertFalse(status["merge_allowed"])
+        self.assertFalse(status["approve_allowed"])
+
+    def test_server_tool_blocks_merge_on_live_namespace_broken(self):
+        result = gitea_mcp_server.gitea_assess_review_merge_state_machine(
+            state_completion=self._merge_ready_completion(),
+            pre_merge_gates=self._all_gates(),
+            live_namespace_broken=True,
+        )
+        self.assertTrue(result["blockers"]["block"])
+        self.assertFalse(result["merge"]["allowed"])
+
+    def test_classify_verdict_bridges_into_merge_block(self):
+        # The classify verdict is the intended feed for live_namespace_broken.
+        verdict = mcp_namespace_health.classify_namespace_probe(
+            "gitea-merger",
+            registered_tools=["gitea_whoami", "gitea_adopt_merger_pr_lease"],
+            probe_result={"success": False, "error": "client is closing: EOF"},
+            process={"pid": 555, "profile": "prgs-merger"},
+            probe_source="client_namespace",
+        )
+        self.assertTrue(verdict["blocks_merge_workflow"])
+        blocked = rmsm.can_merge(
+            self._merge_ready_completion(),
+            pre_merge_gates=self._all_gates(),
+            live_namespace_broken=verdict["blocks_merge_workflow"],
+        )
+        self.assertFalse(blocked["allowed"])
+
+    def test_offline_spawn_does_not_authorize_mutation_gate(self):
+        gitea_mcp_server.gitea_assess_mcp_namespace_health(
+            "gitea-merger",
+            registered_tools=["gitea_whoami"],
+            probe_result={"success": True, "result": {}},
+            probe_source="offline_spawn",
+        )
+        gate = gitea_mcp_server._live_namespace_health_gate("merge_pr")
+        self.assertTrue(gate)
+        self.assertTrue(any("offline_spawn" in r or "client_namespace" in r for r in gate))
+
+    def test_client_namespace_healthy_clears_mutation_gate(self):
+        gitea_mcp_server.gitea_assess_mcp_namespace_health(
+            "gitea-merger",
+            registered_tools=["gitea_whoami"],
+            probe_result={"success": True, "result": {}},
+            probe_source="client_namespace",
+        )
+        self.assertEqual(gitea_mcp_server._live_namespace_health_gate("merge_pr"), [])
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_review_drafts.py

@@ -0,0 +1,287 @@
+"""Tests for preserving and resuming prepared Gitea review drafts (#609)."""
+
+from __future__ import annotations
+
+import os
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import patch, MagicMock
+
+sys_path_root = str(Path(__file__).resolve().parent.parent)
+if sys_path_root not in sys.path:
+    sys.path.insert(0, sys_path_root)
+
+import mcp_session_state
+import gitea_mcp_server
+import reviewer_pr_lease
+
+
+class TestReviewDrafts(unittest.TestCase):
+    def setUp(self):
+        self._tmpdir = tempfile.TemporaryDirectory()
+        self.state_dir = self._tmpdir.name
+        self._env = patch.dict(
+            os.environ,
+            {
+                mcp_session_state.STATE_DIR_ENV: self.state_dir,
+                mcp_session_state.SESSION_PROFILE_LOCK_ENV: "prgs-reviewer",
+                "GITEA_MCP_PROFILE": "prgs-reviewer",
+                "GITEA_PROFILE_NAME": "prgs-reviewer",
+                "PYTEST_CURRENT_TEST": "1",  # skip runtime stale checks
+            },
+            clear=False,
+        )
+        self._env.start()
+        
+        # Mock workspace binding to pass in test context
+        self._nwb_patch = patch(
+            "gitea_mcp_server.nwb.assess_namespace_mutation_workspace",
+            return_value={"block": False, "mutation_workspace": "/tmp/test-worktree"},
+        )
+        self._nwb_patch.start()
+
+        # Mock authentication headers
+        self._auth_patch = patch(
+            "gitea_mcp_server.get_auth_header",
+            return_value="Bearer mock-token",
+        )
+        self._auth_patch.start()
+
+        self._username_patch = patch(
+            "gitea_mcp_server._authenticated_username",
+            return_value="sysadmin",
+        )
+        self._username_patch.start()
+        
+        # Clear/Mock local session lease in-memory state
+        reviewer_pr_lease.clear_session_lease()
+
+    def tearDown(self):
+        self._username_patch.stop()
+        self._auth_patch.stop()
+        self._nwb_patch.stop()
+        self._env.stop()
+        self._tmpdir.cleanup()
+        reviewer_pr_lease.clear_session_lease()
+
+    @patch("gitea_mcp_server.api_request")
+    def test_save_draft_success(self, mock_api):
+        print("GITEA_MCP_SERVER FILE:", gitea_mcp_server.__file__)
+        print("DIR OF GITEA_MCP_SERVER:", dir(gitea_mcp_server))
+        mock_api.return_value = {
+            "head": {"sha": "headsha1234567890"},
+            "base": {"ref": "master", "sha": "basesha0987654321"},
+        }
+        res = gitea_mcp_server.gitea_save_review_draft(
+            pr_number=587,
+            action="approve",
+            body="Good changes",
+            expected_head_sha="headsha1234567890",
+            validation_commands="pytest tests/",
+            validation_results="all pass",
+            blocker_reason="stale daemon",
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        self.assertTrue(res.get("success"))
+        self.assertEqual(res.get("head_sha"), "headsha1234567890")
+        
+        # Load draft and verify fields
+        draft = mcp_session_state.load_state(
+            kind=mcp_session_state.KIND_REVIEW_DRAFT,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            profile_identity="prgs-reviewer",
+        )
+        self.assertIsNotNone(draft)
+        self.assertEqual(draft.get("pr_number"), 587)
+        self.assertEqual(draft.get("action"), "approve")
+        self.assertEqual(draft.get("body"), "Good changes")
+        self.assertEqual(draft.get("validation_commands"), "pytest tests/")
+        self.assertEqual(draft.get("validation_results"), "all pass")
+        self.assertEqual(draft.get("blocker_reason"), "stale daemon")
+        self.assertEqual(os.path.realpath(draft.get("worktree_path")), os.path.realpath("/tmp/test-worktree"))
+
+    @patch("gitea_mcp_server.api_request")
+    @patch("gitea_mcp_server._fetch_pr_comments")
+    @patch("gitea_mcp_server.gitea_submit_pr_review")
+    def test_resume_draft_and_submit_success(self, mock_submit, mock_comments, mock_api):
+        # 1. Save draft
+        mock_api.return_value = {
+            "state": "open",
+            "head": {"sha": "headsha1234567890"},
+            "base": {"ref": "master", "sha": "basesha0987654321"},
+        }
+        
+        gitea_mcp_server.gitea_save_review_draft(
+            pr_number=587,
+            action="approve",
+            body="Good changes",
+            expected_head_sha="headsha1234567890",
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        
+        # Seed local session lease
+        reviewer_pr_lease.record_session_lease({
+            "pr_number": 587,
+            "session_id": "session-1234",
+        })
+        
+        # Mock Gitea comments to return active reviewer lease owned by us
+        mock_comments.return_value = [
+            {
+                "id": 1,
+                "user": {"username": "sysadmin"},
+                "body": (
+                    "<!-- mcp-review-lease:v1 -->\n"
+                    "repo: Scaled-Tech-Consulting/Gitea-Tools\n"
+                    "pr: #587\n"
+                    "reviewer_identity: sysadmin\n"
+                    "profile: prgs-reviewer\n"
+                    "session_id: session-1234\n"
+                    "phase: claimed\n"
+                ),
+            }
+        ]
+        
+        mock_submit.return_value = {"performed": True, "success": True}
+        
+        # 2. Resume draft
+        res = gitea_mcp_server.gitea_resume_review_draft(
+            pr_number=587,
+            submit=True,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        
+        self.assertTrue(res.get("success"))
+        self.assertTrue(res.get("marked_ready"))
+        self.assertTrue(res.get("submitted"))
+        mock_submit.assert_called_once()
+        
+        # Verify draft was deleted after successful submit
+        draft = mcp_session_state.load_state(
+            kind=mcp_session_state.KIND_REVIEW_DRAFT,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            profile_identity="prgs-reviewer",
+        )
+        self.assertIsNone(draft)
+
+    @patch("gitea_mcp_server.api_request")
+    @patch("gitea_mcp_server._fetch_pr_comments")
+    def test_resume_draft_fails_checks(self, mock_comments, mock_api):
+        # Save a draft
+        mock_api.return_value = {
+            "state": "open",
+            "head": {"sha": "headsha1234567890"},
+            "base": {"ref": "master", "sha": "basesha0987654321"},
+        }
+        gitea_mcp_server.gitea_save_review_draft(
+            pr_number=587,
+            action="approve",
+            body="Good changes",
+            expected_head_sha="headsha1234567890",
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        
+        # Seed local session lease
+        reviewer_pr_lease.record_session_lease({
+            "pr_number": 587,
+            "session_id": "session-1234",
+        })
+        
+        # Mock Gitea comments to return active reviewer lease owned by us
+        mock_comments.return_value = [
+            {
+                "id": 1,
+                "user": {"username": "sysadmin"},
+                "body": (
+                    "<!-- mcp-review-lease:v1 -->\n"
+                    "repo: Scaled-Tech-Consulting/Gitea-Tools\n"
+                    "pr: #587\n"
+                    "reviewer_identity: sysadmin\n"
+                    "profile: prgs-reviewer\n"
+                    "session_id: session-1234\n"
+                    "phase: claimed\n"
+                ),
+            }
+        ]
+        
+        # Case A: PR closed
+        mock_api.return_value = {
+            "state": "closed",
+            "head": {"sha": "headsha1234567890"},
+            "base": {"ref": "master", "sha": "basesha0987654321"},
+        }
+        res = gitea_mcp_server.gitea_resume_review_draft(
+            pr_number=587,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        self.assertFalse(res.get("success"))
+        self.assertIn("PR #587 is not open", res.get("reasons")[0])
+        
+        # Case B: Head changed
+        mock_api.return_value = {
+            "state": "open",
+            "head": {"sha": "headsha_NEW"},
+            "base": {"ref": "master", "sha": "basesha0987654321"},
+        }
+        res = gitea_mcp_server.gitea_resume_review_draft(
+            pr_number=587,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        self.assertFalse(res.get("success"))
+        self.assertIn("PR head SHA changed", res.get("reasons")[0])
+        
+        # Case C: Target branch changed
+        mock_api.return_value = {
+            "state": "open",
+            "head": {"sha": "headsha1234567890"},
+            "base": {"ref": "master", "sha": "basesha_NEW"},
+        }
+        res = gitea_mcp_server.gitea_resume_review_draft(
+            pr_number=587,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/test-worktree",
+        )
+        self.assertFalse(res.get("success"))
+        self.assertIn("target branch SHA changed", res.get("reasons")[0])
+        
+        # Case D: Worktree mismatch
+        mock_api.return_value = {
+            "state": "open",
+            "head": {"sha": "headsha1234567890"},
+            "base": {"ref": "master", "sha": "basesha0987654321"},
+        }
+        res = gitea_mcp_server.gitea_resume_review_draft(
+            pr_number=587,
+            remote="prgs",
+            org="Scaled-Tech-Consulting",
+            repo="Gitea-Tools",
+            worktree_path="/tmp/different-worktree",
+        )
+        self.assertFalse(res.get("success"))
+        self.assertIn("worktree binding mismatch", res.get("reasons")[0])