docs(qual): resolve late PLAN3 review findings

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/CHUNK_MAP.md

@@ -20,13 +20,14 @@ remain stopped historical experiments. Do not resume them.
 
 | Chunk | Purpose | Risk | State |
 |---|---|---:|---|
-| `WS-QUAL-001-PLAN3` | Replace percentage-only closure with behavior/mutation assurance | L1 | Planning in progress |
-| `WS-QUAL-001-04M` | Pilot pinned changed-scope mutation evidence without a score gate | L1 | Proposed after PLAN3 merge and explicit instruction |
+| `WS-QUAL-001-PLAN3` | Replace percentage-only closure with behavior/mutation assurance | L1 | Merged PR #272; late review corrected by PLAN3R1 |
+| `WS-QUAL-001-PLAN3R1` | Resolve five valid late CodeRabbit findings from PR #272 | L1 | Corrective planning chunk in progress |
+| `WS-QUAL-001-04M` | Pilot pinned changed-scope mutation evidence without a score gate | L1 | Proposed after PLAN3R1 merge and explicit instruction |
 | `WS-QUAL-001-05M` | Add calibrated blocking behavior-mutation policy | L1 | Proposed only after accepted 04M hosted evidence and explicit instruction |
 
 ## Dependency rule
 
-`PLAN3 -> 04M -> human calibration checkpoint -> 05M`.
+`PLAN3 -> PLAN3R1 -> 04M -> human calibration checkpoint -> 05M`.
 
 Each chunk maps to one PR. `04M` may prove that the candidate engine or target
 strategy is unsuitable and stop without `05M`. Planning does not pre-authorize

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/PLAN.md

@@ -9,9 +9,10 @@ two independently reviewed implementation chunks.
 
 Add one exactly pinned mutation engine and a Workstream-owned policy wrapper.
 The wrapper derives a closed set of eligible production targets from the git
-delta or from an explicit test-only behavior claim. It selects the smallest
-owner test set, runs under a hard timeout, and emits machine-readable exact-head
-evidence.
+delta and always mutates those targets. It then adds any explicit test-only
+behavior claims, each with owning test nodes; a claim cannot replace eligible
+changed-production mutation. The wrapper selects the smallest owner test set,
+runs under a hard timeout, and emits machine-readable exact-head evidence.
 
 The pilot does not block on mutation score. It does block on infrastructure
 failure, malformed evidence, target escape, missing claimed tests, ordinary
@@ -31,11 +32,12 @@ Only after pilot review, add a separate required check for eligible changed
 production logic and test-only PRs that claim behavioral improvement. The gate
 uses the pilot's deterministic target and evidence grammar.
 
-There is no repository-wide mutation percentage. Every eligible survivor
-blocks unless it has a narrow, typed classification accepted by policy (for
-example, demonstrably equivalent or non-behavioral). Missing, stale, broad, or
-free-form exclusions fail closed. Timeout and tool errors do not count as
-killed mutants and cannot silently pass.
+There is no repository-wide mutation percentage. The policy must enumerate
+every engine status, including killed, survived, suspicious, timeout, error,
+and excluded. Each status either blocks or maps to an independently
+verified, typed classification accepted by policy (for example, demonstrably
+equivalent or non-behavioral). Missing, stale, broad, free-form, or unrecognized
+classifications fail closed. No status may pass implicitly.
 
 ## Behavior ownership
 
@@ -57,9 +59,11 @@ observable outcomes. Test-only non-behavioral maintenance uses a narrow typed
 classification defined by policy rather than free-form exemption text.
 
 Test-only changes that claim coverage or stronger behavior must provide this
-mapping. Documentation-only, fixture-only, generated-code, and non-behavioral
-maintenance changes are outside mutation selection but remain subject to
-ordinary tests and review.
+mapping. Fixture-only changes are non-behavioral only when policy evidence
+proves they cannot affect test selection, test inputs, or assertion behavior;
+otherwise they require a bounded behavior claim. Documentation-only,
+generated-code, and independently verified non-behavioral maintenance changes
+remain outside mutation selection but subject to ordinary tests and review.
 
 ## Runtime and isolation strategy
 
@@ -77,9 +81,13 @@ ordinary tests and review.
 
 - Pin the selected engine and its transitive dependency closure with hashes.
 - Do not add the mutation engine to production dependencies.
-- Install the engine only from `scripts/mutation-requirements.txt` with
-  `pip install --require-hashes`; `backend/pyproject.toml` may contain tool
-  configuration but cannot add the engine to ordinary dev extras.
+- Obtain the approved mutation package, version, and hash authority from the
+  protected base revision, an equivalently protected allowlist, or a protected
+  prebuilt runtime—never from a manifest editable by the pull request. If
+  `scripts/mutation-requirements.txt` is used, install only from its trusted
+  base-revision copy with `pip install --require-hashes`;
+  `backend/pyproject.toml` may contain tool configuration but cannot add the
+  engine to ordinary dev extras.
 - Never apply mutants to the contributor worktree in CI.
 - Upload bounded result evidence without source secrets, environment values,
   database contents, or artifact payloads.
@@ -112,11 +120,17 @@ errors, missing evidence, stale evidence, and target escape all stop the gate.
 
 ## Dependency order
 
-`PLAN3 -> 04M pilot -> human calibration checkpoint -> 05M blocking gate`.
+`PLAN3 -> PLAN3R1 -> 04M pilot -> human calibration checkpoint -> 05M blocking
+gate`.
 `05M` cannot begin from planning alone; it requires accepted exact hosted pilot
 evidence and a new explicit human instruction.
 
 ## Stop
 
 Planning does not install a mutation engine, change a workflow, or change a
-coverage threshold. Stop after the PLAN3 PR and human checkpoint.
+coverage threshold. Stop after the PLAN3R1 correction PR. Do not start `04M`
+without separate explicit human instruction.
+
+After `04M`, stop at the human calibration checkpoint. Do not start `05M`
+without accepted exact hosted pilot evidence and a new explicit human
+instruction.

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/STATUS.md

@@ -12,8 +12,11 @@ new or materially changed subsystem checks remain blocking at 90 percent.
 
 ## Current gate
 
-`WS-QUAL-001-PLAN3` is planning only. It replaces the unstarted 04R global-floor
-switch with a two-stage behavior/mutation assurance proposal:
+`WS-QUAL-001-PLAN3` merged through PR #272. `WS-QUAL-001-PLAN3R1` is a
+planning-only correction for five valid CodeRabbit findings that arrived before
+the merge but were not addressed. It must merge before `04M` starts.
+
+The corrected proposal remains two-stage:
 
 1. `04M` — bounded, pinned, changed-scope mutation pilot with complete evidence
    and no blocking score.
@@ -26,6 +29,6 @@ implemented.
 
 ## Stop condition
 
-Stop after PLAN3 planning review and PR. Do not start 04M automatically. Do not
-start 05M without accepted exact hosted pilot evidence and a new human
+Stop after the PLAN3R1 correction review and PR. Do not start 04M automatically.
+Do not start 05M without accepted exact hosted pilot evidence and a new human
 instruction.

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/README.md

@@ -4,6 +4,7 @@ Only these PLAN3 records describe possible current work:
 
 - `WS-QUAL-001-PLAN3-behavior-mutation-assurance.md`
 - `WS-QUAL-001-04M-changed-scope-mutation-pilot.md`
+- `WS-QUAL-001-PLAN3R1-late-external-review-correction.md`
 - `WS-QUAL-001-05M-blocking-behavior-mutation-gate.md`
 
 Every other file in this directory is historical evidence from the original

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/WS-QUAL-001-04M-changed-scope-mutation-pilot.md

@@ -40,7 +40,6 @@ scripts/git_delta.py
 scripts/test_git_delta.py
 scripts/workstream_agent_gate.py
 scripts/behavior-claim.schema.json
-scripts/mutation-requirements.txt
 scripts/test_lightweight_agent_gates.py
 .ci/behavior-claims/WS-QUAL-001-04M.json
 .ci/behavior-claims/README.md
@@ -59,22 +58,28 @@ replacement, reduction, or bypass of Backend semantic lanes, API E2E, or fan-in
 full-backend mutation on ordinary PRs
 mutation pragmas or free-form exclusion lists
 production dependency changes
+creation or modification of the protected mutation-tool dependency authority
 pull_request_target, privileged PR-code execution, writable workflow token,
 checkout credentials, secrets in mutation execution, or unpinned Actions
 ```
 
 ## Acceptance criteria
 
 - [ ] One engine and transitive closure are exactly pinned and hash locked as
-      development/CI-only dependencies, installed exclusively from
-      `scripts/mutation-requirements.txt` with `--require-hashes`.
+      development/CI-only dependencies. Pull-request checks obtain the
+      approved package, version, and hash authority from the protected base
+      revision (or an equivalently protected allowlist or prebuilt runtime),
+      never from a requirements manifest editable by the pull request.
+- [ ] That protected dependency authority exists before the 04M branch starts;
+      04M cannot introduce or modify it. If no approved authority exists, 04M
+      stops for a separate bounded prerequisite rather than installing a tool.
 - [ ] `backend/pyproject.toml` contains configuration only; the mutation engine
       is absent from production dependencies and ordinary dev extras.
-      `scripts/mutation-requirements.txt` is the sole mutation-tool dependency
-      authority; `backend/uv.lock` remains unchanged and is not a second install
-      path.
-- [ ] Deterministic policy selects eligible changed targets or validates a
-      bounded test-only behavior claim with explicit owning test nodes.
+      `backend/uv.lock` remains unchanged and is not a second install path.
+- [ ] Deterministic policy always selects and mutates eligible changed
+      production targets, then adds any bounded test-only behavior claims with
+      explicit owning test nodes; a claim cannot replace eligible target
+      mutation.
 - [ ] Git-delta discovery extracts one shared `scripts/git_delta.py` primitive
       reused by `scripts/workstream_agent_gate.py` and mutation policy, and
       mutation evidence mirrors the

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/WS-QUAL-001-05M-blocking-behavior-mutation-gate.md

@@ -56,10 +56,12 @@ production behavior, migration, or dependency changes
 
 - [ ] Eligibility and evidence grammar are unchanged from accepted pilot proof
       unless a separately reviewed correction is explicit.
-- [ ] Every eligible surviving mutant blocks by default.
+- [ ] Policy enumerates every engine status, including killed, survived,
+      suspicious, timeout, error, and excluded. Each status blocks or maps
+      to an independently verified, typed policy classification.
 - [ ] Any allowed classification is narrow, typed, evidence-bound, and tested;
-      missing, stale, broad, or free-form classifications fail closed.
-- [ ] Timeout, suspicious, and error outcomes never count as killed.
+      missing, stale, broad, free-form, or unrecognized classifications fail
+      closed, and no status passes implicitly.
 - [ ] Test-only behavior/coverage claims cannot bypass target mutation.
 - [ ] `CONTRIBUTING.md` and the canonical claim README/schema/example explain
       when a claim is required, the permitted typed non-behavioral cases, local

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/WS-QUAL-001-PLAN3R1-late-external-review-correction.md

@@ -0,0 +1,99 @@
+# Chunk Contract: WS-QUAL-001-PLAN3R1 — Late External Review Correction
+
+## Parent initiative
+
+`WS-QUAL-001` — Behavior And Mutation Assurance
+
+## Goal
+
+Correct the five valid CodeRabbit findings that arrived before PR #272 merged
+but were not addressed before the branch was deleted.
+
+## Why this chunk exists
+
+PR #272 changed planning only, so no unsafe mutation runtime was deployed.
+However, its merged plan leaves ambiguity in dependency custody, mutation
+outcome handling, fixture-only classifications, target selection, and exact
+Backend evidence binding. Those ambiguities must be removed before `04M` may
+start.
+
+## Risk class
+
+L1 — CI/test policy planning correction.
+
+## Machine scope
+
+```chunk-scope-json
+{
+  "schema_version": 1,
+  "chunk_id": "WS-QUAL-001-PLAN3R1",
+  "allowed_paths": [
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/CHUNK_MAP.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/PLAN.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/STATUS.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/README.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/WS-QUAL-001-04M-changed-scope-mutation-pilot.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/WS-QUAL-001-05M-blocking-behavior-mutation-gate.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/chunks/WS-QUAL-001-PLAN3R1-late-external-review-correction.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/reviews/WS-QUAL-001-PLAN3-pr-trust-bundle.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/reviews/WS-QUAL-001-PLAN3R1-external-review-response.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/reviews/WS-QUAL-001-PLAN3R1-internal-review-evidence.md",
+    ".agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/reviews/WS-QUAL-001-PLAN3R1-pr-trust-bundle.md",
+    ".agent-loop/merge-intents/WS-QUAL-001-PLAN3R1.json"
+  ],
+  "forbidden_paths": [
+    ".github/**",
+    "backend/**",
+    "scripts/**"
+  ],
+  "verification_commands": [
+    "markdown-links",
+    "stale-wording",
+    "lightweight-agent-gates",
+    "git-diff-check"
+  ]
+}
+```
+
+## Not allowed
+
+```text
+workflow, dependency, backend, test, or mutation implementation
+coverage-threshold changes
+automatic start of 04M or 05M
+changes outside the WS-QUAL-001 correction evidence and merge intent
+```
+
+## Acceptance criteria
+
+- [ ] PR code cannot choose or modify the mutation-tool dependency authority.
+- [ ] Eligible changed production targets are always selected; bounded
+      test-only behavior claims are additive and name owning test nodes.
+- [ ] Every engine outcome fails closed or has an independently verified typed
+      policy classification.
+- [ ] Fixture-only changes require proof before receiving a non-behavioral
+      classification.
+- [ ] PLAN3 Backend evidence names both exact run and commit.
+- [ ] All five late comments are recorded and resolved before `04M` starts.
+
+## Required reviewers
+
+- senior engineering
+- QA/test
+- security/auth
+- product/ops
+- architecture
+- CI integrity
+- docs
+- reuse/dedup
+- test delta
+
+## Human review focus
+
+Confirm this correction closes the five late comments without implementing or
+pre-authorizing mutation CI.
+
+## Stop conditions
+
+Stop if the correction requires executable workflow, dependency, backend, test,
+or mutation changes.

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/reviews/WS-QUAL-001-PLAN3-pr-trust-bundle.md

@@ -28,8 +28,8 @@ quality before implementation.
 
 ## Design chosen
 
-Mutation targets are eligible changed production logic or explicit test-only
-behavior claims. Claims use schema-v1
+Mutation selection always includes eligible changed production logic and then
+adds any explicit test-only behavior claims with owning test nodes. Claims use schema-v1
 `.ci/behavior-claims/<chunk-id>.json`; mutable PR prose cannot widen them.
 `04M` runs independently under hard limits and records complete outcomes.
 `05M` is not authorized until pilot evidence is accepted by a human.
@@ -57,9 +57,9 @@ mutation outcomes are engineering evidence and never product decisions.
 
 ## Acceptance criteria proof
 
-- Current main is recorded from Backend run `30926337804`: 3,162 completed
-  tests, 21,620 / 23,938 coverage (90.316651 percent), 620.264 seconds wall,
-  and 464.471 seconds slowest lane.
+- Current main is recorded from Backend run `30926337804` on commit
+  `5f2baf90`: 3,162 completed tests, 21,620 / 23,938 coverage (90.316651
+  percent), 620.264 seconds wall, and 464.471 seconds slowest lane.
 - Global 78 and protected 90 floors are explicitly preserved.
 - Changed-production and test-only behavior paths are both planned.
 - Strong-vs-weak seeded mutant proof, complete outcome evidence, runtime bounds,
@@ -85,9 +85,9 @@ reviewer session remains open.
 
 ## External review
 
-Agent Gates, CodeRabbit, and human review are pending publication. Backend is
-not required by the planning diff unless GitHub policy schedules it; no Backend
-file changes.
+This section records the pre-publication state of PLAN3. PR #272 later received
+five valid CodeRabbit findings before merge; PLAN3R1 records their disposition
+in `WS-QUAL-001-PLAN3R1-external-review-response.md`. No Backend files changed.
 
 ## Remaining risks
 

.agent-loop/initiatives/WS-QUAL-001-backend-coverage-floor/reviews/WS-QUAL-001-PLAN3R1-external-review-response.md

@@ -0,0 +1,48 @@
+# WS-QUAL-001-PLAN3R1 External Review Response
+
+## Comments addressed
+
+- PR #272 discussion `3714978005`: PR-editable dependency manifests are no
+  longer trusted as mutation-tool authority; the contract requires authority
+  from a protected base revision or an equivalent protected runtime that
+  already exists before 04M and cannot be introduced or modified by 04M.
+- PR #272 discussion `3714978015`: test-only behavior claims are additive and
+  cannot replace mutation of eligible changed production targets.
+- PR #272 discussion `3714978020`: every engine status must block or map to an
+  independently verified typed classification; implicit passing is forbidden.
+- PR #272 discussion `3714978023`: fixture-only changes are exempt only after
+  evidence proves they cannot influence selection, inputs, or assertions.
+- PR #272 discussion `3714978026`: PLAN3 Backend evidence now binds run
+  `30926337804` to commit `5f2baf90`.
+
+## PR #278 follow-up comments addressed
+
+- Standardized the canonical mutation status label as `error` across PLAN,
+  04M evidence, INTENT, DISCOVERY, and the 05M gateway.
+- Separated the PLAN3R1 stop, explicit 04M start, 04M calibration checkpoint,
+  and explicit evidence-bound 05M start.
+- Clarified that dependency authority comes from a protected base revision.
+- Corrected the trust-bundle scope evidence to twelve changed paths.
+
+## Comments deferred
+
+None.
+
+## Human decisions needed
+
+None. This chunk corrects merged planning and does not implement mutation CI.
+
+## Commands rerun
+
+- `python3 scripts/check_markdown_links.py`
+- `python3 scripts/check_stale_workstream_wording.py`
+- `python3 scripts/check_stale_authorization_docs.py`
+- `python3 scripts/check_stale_artifact_contracts.py`
+- `PYTEST_DISABLE_PLUGIN_AUTOLOAD=1 python3 -m pytest -q scripts/test_lightweight_agent_gates.py`
+- `git diff --check`
+
+## Remaining risks
+
+The mutation engine and exact executable policy remain intentionally undecided
+until separately authorized `WS-QUAL-001-04M` implementation and hosted pilot
+evidence.