diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F31-adr-scope-reality-divergence.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F31-adr-scope-reality-divergence.md
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+---
+catalogue_id: F31
+title: "ADR scope-reality divergence — batch frame over-scopes due to missing pre-dispatch source verification"
+family: F1-Sediment (verification-gap sub-form)
+severity: P1
+status: ratified_2026-05-16
+empirical_project: Cobrust v0.3.0 Phase F.3 sprint
+cobrust_local_id: F27-candidate (adr-scope-reality-divergence.md)
+date_ratified: 2026-05-16
+second_corroborator: confirmed (P9-A + P9-B independent rediscovery before audit)
+---
+
+# F31 — ADR scope-reality divergence
+
+## Symptoms
+
+A Phase batch ADR (or any strategic-altitude planning document) cites "work
+needed across crates X / Y / Z" without source-code verification. Sub-agents
+dispatched against the ADR re-discover at spike time that the work is already
+partly or fully shipped. They either:
+
+- Pivot scope on the branch (organic recovery — correct, but wastes spike-time)
+- Implement redundantly (regression — incorrect, and wasted dispatch cost)
+
+Two or more sub-agents independently re-discover the same divergence,
+confirming that the gap is structural (not an individual agent oversight).
+
+## Root cause
+
+Strategic-altitude authorship is required to write a coherent batch frame. But
+the same altitude is inherently lossy on local source state. The author models
+the codebase's state from memory/prior ADRs rather than live `grep` evidence,
+and memory lags behind recent sprint merges.
+
+This is F1-family: the rule "verify before scoping" exists as common sense but
+has no enforcement gate at ADR-authorship time. Without an explicit
+"pre-dispatch verification commit", the gap propagates to every sub-agent
+dispatched against the stale scope.
+
+## SOP fix — ADR pre-dispatch source-code verification gate
+
+Add this gate to every batch-frame ADR authorship:
+
+**Phase 1 — source verification (mandatory, in the same commit as the ADR)**:
+1. Run at least 3 representative `grep -nE` calls against the cited crates
+   (symbol search, not file-existence check).
+2. For each claimed "work needed", record the grep result in ADR §"Verification"
+   section: either "not found — gap confirmed" or "found at `file::symbol` —
+   gap already shipped".
+3. Only scope the sub-ADR (sub-sprint) for unconfirmed gaps.
+
+**Phase 2 — sub-dispatch (once Phase 1 committed)**:
+Dispatch sub-agents with a reference to the verification commit. The sub-agent's
+§"Done means" criteria must start with "confirm gap still exists at HEAD SHA".
+
+The two-phase pattern ensures the verification is co-located with the ADR,
+visible to every future reader, and forms a diff-based audit trail.
+
+## Evidence
+
+Cobrust ADR-0050 Phase F.3 batch, 2026-05-16 (SHA `891d235`):
+
+- ADR scoped 5 P0 features as "work needed".
+- Pre-impl audit (read-only opus `afe53e8f`) + two independent P9 spike commits
+  (`1998dbe`, `909811f`) found that 3/5 features were already substantially shipped
+  at HEAD `30cf2b2`:
+  - `break`/`continue` — fully shipped end-to-end (lexer → AST → MIR → Cranelift).
+  - `for`-loop protocol — operational over `list[i64]` + `list[str]` since ADR-0044.
+  - `f64` — 80% shipped; remaining gap was a D2-sonnet scope, not D4-opus-1-week.
+- Only `Str`-ownership debt (ADR-0050c) and `dict` (Wave 3) survived as honestly
+  large work.
+- Batch estimate revised from 4-5 weeks to 2-3 weeks after correction.
+- Two redundant re-discoveries (P9-A + P9-B) before the dedicated pre-impl audit
+  confirmed the pattern is structural, not accidental.
+
+## Counter-pattern
+
+Instead of:
+```
+Write batch ADR → dispatch sub-agents → sub-agents re-discover scope
+```
+
+Use:
+```
+Write batch ADR frame → run 3+ verification greps → amend ADR with results
+→ dispatch sub-agents against verified gaps only
+```
+
+The pre-dispatch source verification gate converts a passive documentation
+convention into an active confirmation step.
+
+## Cross-references
+
+- F34 (numeric-anchor degradation) — sibling; F31 is a scope-gap at ADR
+  authorship time; F34 is a symbol-anchor gap at doc maintenance time.
+- F32 (wave-2 cascade discovery deficit) — downstream: when F31 produces
+  over-scoped sub-ADRs, F32-style cascade bugs surface during the impl sprint
+  because the over-scoped design didn't enumerate all consumers.
+- Cobrust finding: `docs/agent/findings/adr-scope-reality-divergence.md`
+- Cobrust ADR: `docs/agent/adr/0050-phase-f3-language-completeness-batch.md`
+  §"Amendment 2026-05-16"
+
+## Status
+
+Ratified 2026-05-16. Two-phase gate adopted in Cobrust CTO runbook for all
+batch-frame ADR authorship. Second-corroborator requirement satisfied by
+independent P9-A + P9-B rediscoveries.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F32-pair-pattern-impl-gap-single-layer-subagent.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F32-pair-pattern-impl-gap-single-layer-subagent.md
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+---
+catalogue_id: F32
+title: "PAIR pattern impl gap under single-layer sub-agent architecture"
+family: methodology-gap (PAIR-topology sub-form)
+severity: P0 (methodology integrity)
+status: ratified_2026-05-16
+empirical_project: Cobrust v0.3.0 Phase F.3 sprint
+cobrust_local_id: F28-candidate (adsd-pair-pattern-impl-gap.md)
+date_ratified: 2026-05-16
+second_corroborator: structural (platform inspection confirms no Agent tool in sub-agents)
+---
+
+# F32 — PAIR pattern impl gap under single-layer sub-agent architecture
+
+## Symptoms
+
+ADSD §"Dev/test pair pattern" prescribes "P9 spawns P7-TEST first, then P9
+reviews the corpus, then P9 spawns P7-DEV". A project adopts this ceremony but
+sub-agents (P9-level) do not have the `Agent` tool — the platform only exposes
+it to the top-level orchestrator (P10/main session).
+
+Result: the PAIR ceremony is **structurally unimplementable as written** on
+single-layer platforms. Sub-agents either:
+
+- Silently ignore the instruction and perform TEST + DEV as a single-Opus pass
+  (ceremonial PAIR, same-agent bias retained)
+- Write sequential "phases" within their own context (still single agent,
+  bias not eliminated)
+- Send a message back to the orchestrator requesting a new dispatch
+  (workable, but high coordination overhead)
+
+The same-agent bias ADSD designed PAIR to prevent is present even when the
+PAIR ceremony is nominally followed.
+
+## Root cause
+
+ADSD's PAIR pattern was written assuming a multi-layer agent architecture where
+P9 can recursively dispatch P7-tier agents. Under Claude Code (and any other
+single-layer orchestration platform), sub-agents have a constrained tool set
+that excludes the Agent/dispatch tool. The PAIR ceremony cannot be implemented
+by the sub-agent itself.
+
+Same-agent bias: when one agent writes both the failing tests and the
+implementation, the tests tend to mirror the author's mental model rather than
+independently probe the spec. Constitution §6 "test-first" is honored in form
+but not in spirit.
+
+## SOP fix — P10-direct PAIR dispatch
+
+On single-layer platforms, the orchestrator (P10/main session) MUST directly
+dispatch both TEST and DEV agents as parallel calls:
+
+1. **P10 dispatches TEST agent**: "Write failing test corpus only; forbidden
+   to write impl; report `[TEST-CORPUS-READY]` with file paths + assertion
+   counts + `cargo test` fail count."
+2. **P10 reviews TEST corpus** (~5-10 min): coverage / spec-faithfulness /
+   edge cases. Sends amendment message if needed.
+3. **P10 dispatches DEV agent** with TEST's commit SHA + corpus paths as
+   **required input**. DEV implements until `cargo test` 0-fails.
+4. **P10 verifies** all gates green + merges.
+
+**When NOT to use P10-direct PAIR** (P9 single-Opus is fine):
+- ADR-authoring sprints (doc-only, no impl)
+- Strategic decomposition where there's no impl yet
+- Doc-only edits, runbook updates, frontmatter stamps
+- Pre-impl audits (read-only is correct)
+
+**Coordination overhead trade-off**: P10-direct PAIR costs ~2× dispatch
+ceremony per sprint. For load-bearing sprints (contract-bearing public API,
+novel semantics, multi-crate refactor) the methodological guarantee is worth
+the cost. For trivial sprints (D1 well-scoped doc fix), single-sonnet is fine.
+
+## Evidence
+
+Cobrust Phase F.3 Wave 1, 2026-05-16:
+
+- `cto_operations_runbook.md` §"Dev/test pair pattern" prescribed
+  "P9-spawns-P7-TEST-then-P7-DEV".
+- 3 P9 Opus sprint dispatches with full PAIR ceremony in the prompt.
+- Tool surface inspection confirmed: P9 sub-agents have no `Agent` tool.
+- 2/3 sprints (P9-A break/continue `1998dbe`, P9-B for-loop `909811f`)
+  executed as single-Opus contract-seal + corpus. The PAIR ceremony was
+  ceremonial — no double-blind separation achieved.
+- 1/3 sprint (P9-C dict design `8466433`) was ADR-only and didn't need PAIR.
+- User surfaced this gap 2026-05-16 during Wave 1 dispatch review.
+- Runbook updated 2026-05-16 to mark P9-PAIR as structurally invalid and
+  replace with P10-direct PAIR for D1-D3 / D5 sprints.
+
+## Platform dependency note
+
+This failure mode is specific to platforms that do not expose the Agent/dispatch
+tool to sub-agents. On platforms that support recursive agent dispatch (e.g.
+AutoGen, CrewAI, future Claude Code multi-layer), P9 can dispatch P7 as
+originally written. ADSD methodology should declare PAIR's
+implementation-layer responsibility explicitly per platform tier:
+
+- Multi-layer platform: P9 dispatches P7-TEST + P7-DEV as written.
+- Single-layer platform: Orchestrator (P10) directly dispatches TEST + DEV;
+  P9 layer reserved for ADR-authoring + strategic decomposition.
+
+## Cross-references
+
+- F33 (agent self-disciplinary rule skip) — F32 is the structural reason PAIR
+  discipline breaks: the rule is there, but the agent physically cannot execute it.
+- F36 (TEST corpus exit-0 claim drift) — downstream: even when P10-direct PAIR
+  runs, F36 shows the TEST corpus clean-claim itself needs independent re-verification.
+- Cobrust finding: `docs/agent/findings/adsd-pair-pattern-impl-gap.md`
+- Cobrust memory: `feedback_adsd_pair_pattern_impl_gap.md`
+- ADR reference: `docs/agent/adr/0050-phase-f3-language-completeness-batch.md`
+  §"Amendment 2026-05-16" §A7
+
+## Status
+
+Ratified 2026-05-16. P10-direct PAIR pattern adopted in Cobrust CTO runbook
+for all D1-D3 / D5 sprints. Cobrust Phase F.3 Wave 2 + Wave 3 used P10-direct
+PAIR as the new standard pattern.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F33-predicate-flip-cascade-discovery-deficit.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F33-predicate-flip-cascade-discovery-deficit.md
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@@ -0,0 +1,117 @@
+---
+catalogue_id: F33
+title: "Predicate-flip cascade discovery deficit — F29-style enumeration misses latent consumers"
+family: cascade-discovery-gap
+severity: P2 (methodology integrity)
+status: ratified_2026-05-16
+empirical_project: Cobrust v0.3.0 Phase F.3 Wave 2 (ADR-0050c Str-ownership)
+cobrust_local_id: F30-candidate (predicate-flip-cascade-discovery-deficit.md)
+date_ratified: 2026-05-16
+second_corroborator: audit teammate a15e69b315007f341 (post-Wave-2)
+---
+
+# F33 — Predicate-flip cascade discovery deficit
+
+## Symptoms
+
+A sub-ADR proposes flipping a shared MIR / codegen / type-system predicate
+(e.g. `is_copy_type(Ty) → bool`, `is_drop_eligible(Ty) → bool`,
+`is_pointer_type(Ty) → bool`). An F29-style §"Consequences" enumeration
+captures direct consumers (all call sites of the predicate found via
+static `grep`).
+
+During implementation, the DEV agent surfaces additional cascade bugs that
+the enumeration missed. These are **latent consumers** — code paths that
+existed in the codebase but were unreachable under the old predicate state.
+Recovery wall-time scales with the latent-consumer set size, not the
+direct-consumer set size.
+
+Signature symptom: the DEV dispatch stalls or runs significantly over time
+budget while triaging cascade bugs serially.
+
+## Root cause
+
+F29-style static `grep` enumeration finds call sites — places in the code
+that call the predicate function. It cannot enumerate:
+
+1. **Placeholder-returning stubs** that were safe under the old predicate
+   (e.g. `lower_constant(Str)` returning `0` — zero overhead when Str was
+   never a non-Copy type; wrong placeholder when Str becomes non-Copy).
+2. **Dispatch sites with IR-level type witnesses** that no longer correlate
+   with MIR type after the flip (e.g. f-string holes dispatching on `i64`
+   Cranelift value-type because Str pointers happen to be `i64` in IR).
+3. **Bookkeeping calls** that had zero-overhead under the old predicate
+   (e.g. `set_param_count` with an off-by-one that produced correct output
+   when the predicate gated off non-Copy local enumeration).
+
+All three classes are invisible to static symbol-search enumeration. They are
+only discoverable via runtime test-failure analysis after the predicate flips.
+
+## SOP fix — shadow-flip dry-run workflow
+
+Every predicate-flip ADR must mandate a "shadow-flip dry-run" during design:
+
+1. **Land the flip behind a feature flag** in the design-only ADR commit
+   (e.g. `#[cfg(predicate_flip_NN)]` or a runtime config toggle).
+2. **Run `cargo test --workspace`** with the flag ON against the current
+   HEAD corpus.
+3. **Classify each new failure**:
+   - Direct-consumer (enumerated in §"Consequences"): expected.
+   - Latent-consumer (new, not enumerated): add to §"Consequences addendum".
+   - Genuine semantic breakage from the flip: note in ADR, fix design or scope.
+4. **Enumerate all latent consumers** in a §"Consequences addendum" before
+   removing the flag.
+5. The pre-flag baseline + post-flag baseline diff IS the complete F29
+   enumeration; the pre-impl audit verifies completeness.
+
+**Cost/benefit**: ~2× design-ADR effort (shadow-flip takes a few hours) pays
+back ~10× in impl wall-time by surfacing latent consumers at design time
+when enumeration-mismatch costs 1 line of doc, not 1 hour of impl debugging.
+
+## Evidence
+
+Cobrust ADR-0050c Wave 2, 2026-05-16:
+
+- ADR-0050c §"Consequences" enumerated **27 direct consumers** via thorough
+  pre-impl audit.
+- Wave 2 DEV agent (`a2056acb07469204f`) surfaced **7 additional latent
+  consumers** as cascade bugs:
+  - `lower_constant(Str)` returning `0` pointer sentinel (M9-era stub)
+  - f-string hole dispatch on `i64` Cranelift type
+  - `set_param_count` off-by-one
+  - 4 additional Wave-2 cascade fixes (per merge `aca5d87`)
+- **Miss rate: 26%** (7 out of 27 enumerated consumers were missed).
+- List[str] DEV recovery agent stalled at 600s mid-investigation; cascade
+  bugs surfaced serially over ~5h recovery wall-time.
+- A shadow-flip dry-run during ADR-0050c design could have surfaced all 7
+  within 1-2h, allowing the impl PAIR DEV to start with a complete enumeration.
+
+## Pattern signal
+
+Watch for F33 when:
+1. A sub-ADR proposes flipping a **shared predicate** (a function returning
+   `bool` that gates MIR / codegen / type-check behavior on type or value shape).
+2. The §"Consequences" enumeration uses **static `grep`** of call sites rather
+   than **runtime-observed** consumer behavior.
+3. The codebase has multiple eras of code (e.g. M9 stubs, earlier-phase paths,
+   compiler extension surfaces) where different eras gated off the predicate
+   differently.
+
+## Cross-references
+
+- F31 (ADR scope-reality divergence) — F33 extends F31's "verify-at-HEAD"
+  discipline to "verify-under-shadow-flip".
+- F34 (wave-2 cascade discovery deficit) — third instance corroboration of
+  same pattern (narrower domain: method-dispatch infrastructure).
+- Cobrust finding:
+  `docs/agent/findings/predicate-flip-cascade-discovery-deficit.md`
+- Cobrust ADR: `docs/agent/adr/0050c-str-ownership.md`
+- Latent consumer findings:
+  `docs/agent/findings/lower-constant-str-zero-pointer-m9-stub.md`,
+  `docs/agent/findings/fstring-hole-mir-type-dispatch.md`
+
+## Status
+
+Ratified 2026-05-16. Shadow-flip dry-run workflow added to Cobrust CTO runbook
+as mandatory for all predicate-flip sub-ADRs. Post-Wave-2 audit teammate
+`a15e69b315007f341` confirmed the 26% miss rate as the second corroborator.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F34-wrapper-type-bidirectional-unify-ambiguous-type-cascade.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F34-wrapper-type-bidirectional-unify-ambiguous-type-cascade.md
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--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F34-wrapper-type-bidirectional-unify-ambiguous-type-cascade.md
@@ -0,0 +1,123 @@
+---
+catalogue_id: F34
+title: "Wrapper-type bidirectional unify produces AmbiguousType cascade in legacy code"
+family: inference-layer-transparency-gap
+severity: P1 (design correctness)
+status: ratified_2026-05-17
+empirical_project: Cobrust v0.3.0 Phase G Wave 1 (ADR-0052a borrow/ref)
+cobrust_local_id: F31-candidate (0052a-wave1-dev-bidirectional-unify-cascade.md)
+date_ratified: 2026-05-17
+second_corroborator: confirmed (two consecutive DEV dispatches v1 + v2 hit identical cascade)
+---
+
+# F34 — Wrapper-type bidirectional unify produces AmbiguousType cascade in legacy code
+
+## Symptoms
+
+A sub-ADR introduces a new type wrapper (e.g. `Ref(T)`, `Mut(T)`,
+`Option(T)` if net-new, `Slice(T)`). The ADR's §"Type inference rule" specifies
+a **bidirectional unify arm**: `Ref(T) ↔ T` — the wrapper and its inner type
+unify in both directions. This is motivated as a "transparency rule" so existing
+code that uses `T` also works with `Ref(T)` automatically.
+
+The first DEV dispatch hits a **142-failure cascade** across all legacy programs
+that have no `Ref(T)` expressions. The cascade is all `AmbiguousType` errors,
+not type mismatches or scope errors. The DEV agent re-scopes, strips the
+bidirectional rule, and hits the **same cascade on the second dispatch** —
+confirming the cascade is from the ADR design itself, not the implementation.
+
+## Root cause
+
+Bidirectional unify says: `Ref(T)` unifies with `T` in both directions. The
+inference table has both arms:
+
+```rust
+// Structural arm — correct, safe:
+(Ref(a), Ref(b)) => unify(a, b)
+
+// Bidirectional arm — the problem:
+(Ref(a), b)     => unify(a, b)   // Ref(T) ↔ T
+(a, Ref(b))     => unify(a, b)   // T ↔ Ref(T)
+```
+
+Effect: type variable `?V` can now be resolved to EITHER `T` OR `Ref(T)` via
+separate valid unifications. When a legacy program has `let x: T = expr`, the
+inference table can bind `?V := T` (correct) AND `?V := Ref(T)` (also valid
+via the bidirectional arm). Resolution becomes non-unique → `AmbiguousType`.
+
+Legacy programs without any `Ref(T)` expression are affected because the
+unification problem is over the entire type variable graph, not per-expression.
+
+## SOP fix — one-way call-site coercion only
+
+When introducing a new wrapper type:
+
+1. **Forbid** `(Wrapper(a), b)` and `(b, Wrapper(a))` unify arms in
+   `infer::unify`. Both directions of cross-wrapper unification are forbidden.
+2. **Allow** only the structural arm: `(Wrapper(a), Wrapper(b)) → unify(a, b)`.
+3. For ergonomic "transparency" at consumption sites: implement a
+   **one-way call-site coercion** at specific binding sites only:
+   - `synth_call_args`: when formal param type is `T` and actual is `Ref(T)`,
+     the type checker drops the `Ref` wrapper locally.
+   - Coercion is (a) local to the call-arg binding, (b) unidirectional
+     (`Ref(T) → T` only, not `T → Ref(T)`), (c) scoped to fn-call arg binding
+     (not `let`, return, arithmetic).
+4. **Pre-dispatch checklist** for wrapper-type sub-ADRs: grep the proposed
+   `infer.rs` diff for non-structural cross-wrapper unify arms; reject in ADR
+   audit if found.
+
+## Evidence
+
+Cobrust ADR-0052a Wave 1, 2026-05-17:
+
+- ADR-0052a §3 + §6 (borrow/ref `&s` form) mandated bidirectional
+  `Ty::Ref(T) ↔ T` unify in `crates/cobrust-types/src/infer.rs`.
+- **DEV v1** (`feature/0052a-dev-rejected-prelude-cascade`): 142 failures
+  including 100+ LC-100 regressions, f64 fstring regression, Phase F.3
+  honest-debt re-fire.
+- **DEV v2** (`feature/0052a-dev-v2`): strict scope, same cascade — confirming
+  the cascade is from the ADR design, not implementation scope-creep.
+- **DEV v3** (`feature/0052a-dev-v3`, merged `6843a33`): replaced bidirectional
+  unify with one-way call-site coercion → **0 non-0052a regressions vs main**.
+- ADR-0052a revised at SHA `bcf9c7d` to document the one-way coercion design
+  and prohibit the bidirectional arm.
+
+Failure distribution for DEV v2 (strict-scope baseline):
+
+| Category | Count |
+|---|---|
+| LC-100 `AmbiguousType` in legacy code | 77 |
+| LC-100 `UseAfterMove` shifted to wrong sites | 23 |
+| 0052a well-typed programs all-fail | 30 |
+| 0052a F30-witness all-fail | 4 |
+| f64 fstring regression | 6 |
+| Phase F.3 honest-debt re-fired | 3 |
+| **Total** | **142** |
+
+## Relationship to F33
+
+F33 (predicate-flip cascade discovery deficit) covers a broader predicate-flip
+class. F34 is the specific inference-layer sub-case:
+
+- F33: shared `bool`-returning predicates that gate execution paths.
+- F34: type-unification arms that, when bidirectional, pollute the inference
+  variable graph across the entire program under type-check.
+
+Both share the root: a design-time decision has non-local consequences that
+only manifest at impl time. F33's shadow-flip dry-run applies equally to F34
+(the dry-run would have surfaced the cascade immediately).
+
+## Cross-references
+
+- F33 (predicate-flip cascade) — sibling; F34 is the type-inference-layer
+  instantiation.
+- Cobrust finding:
+  `docs/agent/findings/0052a-wave1-dev-bidirectional-unify-cascade.md`
+- Cobrust ADR: `docs/agent/adr/0052a-borrow-ref.md` (pre-revision SHA
+  `23cadf6`; revised at `bcf9c7d`)
+
+## Status
+
+Ratified 2026-05-17. One-way call-site coercion design adopted in ADR-0052a
+§3 + §6 + §13 at `bcf9c7d`. Second corroborator: DEV v1 and v2 independently
+hit identical 142-failure cascade from the same root ADR design.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F35-wave2-cascade-discovery-deficit-third-instance.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F35-wave2-cascade-discovery-deficit-third-instance.md
new file mode 100644
index 0000000..9fded07
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F35-wave2-cascade-discovery-deficit-third-instance.md
@@ -0,0 +1,113 @@
+---
+catalogue_id: F35
+title: "Wave-2 cascade discovery deficit — third-instance corroboration of F33 in method-dispatch infrastructure"
+family: cascade-discovery-gap (F33 corroboration)
+severity: P2
+status: ratified_2026-05-17
+empirical_project: Cobrust v0.3.0 Phase G Wave 2 (ADR-0052d-prereq)
+cobrust_local_id: F32-candidate (0052d-prereq-impl-blocker.md)
+date_ratified: 2026-05-17
+second_corroborator: structural (ADR §"Precedence" authorship vs. parser source mismatch)
+---
+
+# F35 — Wave-2 cascade discovery deficit (F33 third-instance corroboration)
+
+## Symptoms
+
+A sub-ADR for method-dispatch infrastructure contains a §"Precedence" clause
+that states "no parser change needed: existing path already produces the
+required AST shape." The DEV agent implements the method-dispatch additions
+and hits a structural parser blocker — the borrow-operand validator explicitly
+rejects the very AST shape the §"Precedence" clause claimed was already
+supported.
+
+This is the third instance of the same cascade-discovery deficit pattern
+(F33 first instance: `Str`-ownership predicate flip; F34 second instance:
+bidirectional unify; F35: parser-cap boundary in method-dispatch prereq).
+
+## Root cause
+
+The ADR's §"Precedence with 0052a `&s`" was authored as **forward-looking
+reasoning** ("the design will produce this shape") rather than **verified
+current-state** ("at current HEAD, the parser accepts this"). The author
+ran a logical deduction on the parser structure; the deduction was correct
+for the _intended_ design but incorrect for the _current_ implementation
+which had a Wave-1 cap that blocked the shape.
+
+Structural asymmetry: ADR authors reason about intended system state; the
+DEV agent implements against actual source state. Any divergence between
+intended and actual state produces a blocker that appears only at impl time.
+
+## SOP fix — forward-looking ADR text must be flagged
+
+Add a tagging convention to ADR text:
+
+```markdown
+> **[VERIFIED-AT-HEAD]** The parser admits `&(s.method())` at call site
+> `parser.rs::validate_borrow_operand` — grep confirms `Call` is accepted.
+
+vs.
+
+> **[FORWARD-LOOKING]** Once ADR-0052d ships, the parser will admit
+> `&(s.method())` by extending `validate_borrow_operand` to accept method-form.
+```
+
+Any ADR clause about a "no parser change needed" or "existing path already
+handles X" assertion must be tagged `[VERIFIED-AT-HEAD]` with a grep result
+OR tagged `[FORWARD-LOOKING]` acknowledging a future dependency.
+
+The DEV agent's dispatch contract should require: "for any `[VERIFIED-AT-HEAD]`
+clause in the ADR, re-verify the claim at current branch HEAD before
+implementing against it."
+
+## Evidence
+
+Cobrust ADR-0052d-prereq Wave 2, 2026-05-17:
+
+- ADR-0052d-prereq §"Precedence with 0052a `&s`" (lines 117-121) stated:
+  > "No parser change needed: the existing `parser.rs:1239-1249` Attribute
+  > production + `parser.rs:1105-1110` borrow-operand validator already
+  > produce `Unary(Borrow, Call(Attr(s, "method"), args))` for `&s.method(args)`."
+
+- Actual source (verified at HEAD `1643776` on `feature/0052d-prereq-dev`):
+  `crates/cobrust-frontend/src/parser.rs::validate_borrow_operand` at line
+  1134-1139 explicitly rejects `ExprKind::Call { .. }` with error message:
+  > "borrow of a call-result is not supported in Wave-1 (ADR-0052a §8 cap)"
+
+- Test `f30wit_method_03_borrow_precedence_binds_tighter_than_method_call`
+  fails at parse time with this error.
+
+- DEV correctly filed the blocker finding and deferred `f30wit_method_03` to
+  the ADR-0052d follow-up sprint (Path C), rather than making unauthorized
+  parser changes.
+
+## What DEV did right
+
+The DEV agent's response to this F35 instance was correct:
+
+1. Hit the blocker; recognized it as outside the dispatch scope.
+2. Filed `findings/0052d-prereq-impl-blocker.md` immediately.
+3. Did NOT make unauthorized parser changes to fix the test.
+4. Deferred the failing test with a clear ADR forward-reference.
+5. Shipped all other method-dispatch tests green (2/3 `f30wit_method` + all
+   25 well-typed + 13 ill-typed + 5 e2e tests).
+
+This is the intended "STOP-and-file" behavior. The finding is about the
+upstream ADR authoring process (forward-looking claim not tagged), not the
+DEV agent's handling.
+
+## Cross-references
+
+- F33 (predicate-flip cascade discovery deficit) — first instance; F35 is
+  the third corroboration of the same pattern across different domains.
+- F34 (wrapper-type bidirectional unify) — second instance.
+- Cobrust finding: `docs/agent/findings/0052d-prereq-impl-blocker.md`
+- Cobrust ADR: `docs/agent/adr/0052d-prereq-method-dispatch.md`
+  §"Precedence with 0052a `&s`" (stale claim documented)
+
+## Status
+
+Ratified 2026-05-17. `[VERIFIED-AT-HEAD]` vs `[FORWARD-LOOKING]` tagging
+convention proposed for Cobrust ADR authoring standard. Third-instance
+corroboration (after F33 and F34) validates the cascade-discovery-deficit
+pattern is a systemic ADSD failure mode, not project-specific.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F36-agent-self-disciplinary-rule-skip.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F36-agent-self-disciplinary-rule-skip.md
new file mode 100644
index 0000000..e44ad32
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F36-agent-self-disciplinary-rule-skip.md
@@ -0,0 +1,144 @@
+---
+catalogue_id: F36
+title: "Agent self-disciplinary rule skip when judged low-risk"
+family: F1-Sediment (rule-introduction/rule-erosion sub-family)
+severity: P1 (discipline integrity)
+status: ratified_2026-05-18
+empirical_project: Cobrust v0.3.0 Phase H sprint 2026-05-18
+cobrust_local_id: F33-candidate (f33-agent-self-disciplinary-rule-skip.md)
+date_ratified: 2026-05-18
+second_corroborator: confirmed (three independent instances in single session)
+---
+
+# F36 — Agent self-disciplinary rule skip when judged low-risk
+
+## Symptoms
+
+The orchestrator (P10) introduces a discipline rule into memory during session
+S. Later in the same session, the orchestrator encounters case C where rule R
+applies. The orchestrator judges C "low-risk" / "edge-case" / "below-threshold"
+and skips R for C. The skip is not forgetting — it is an active in-session
+risk judgment overriding the rule.
+
+Three structural shapes:
+1. **Rule just introduced, skipped on first application** — the rule was
+   written to address already-empirical pain, but the next instance hasn't
+   yet caused pain, so the rule feels overcautious.
+2. **Rule rationalized as not applying** — "this is an edge case the rule
+   doesn't cover" even though the rule was written precisely for edge cases.
+3. **Scope rationalization** — "this surface is below the threshold" when
+   the cumulative effect of multiple below-threshold edits equals a
+   threshold-crossing single edit.
+
+## Root cause
+
+Memory rules are **passive**. The agent reads them only when the memory file
+is explicitly surfaced or recalled. Between reads, in-context risk judgment
+dominates. The rule was authored to address already-empirical pain. When the
+next instance has not yet caused pain, the rule feels overcautious — so the
+agent suppresses it. This is a sediment-erosion pattern: the rule erodes at
+its first application after introduction.
+
+The structural failure point is **Step 3 in the 5-step erosion loop**:
+
+```
+1. P10 writes rule R into memory at time T
+2. P10 encounters case C at time T+1 where R applies
+3. P10 judges C "low-risk" / "edge-case" / "below-threshold"  ← load-bearing failure
+4. P10 skips R for C
+5a. (Negative path) user catches the skip; P10 acknowledges + re-fires
+5b. (Positive but rare) audit teammate or downstream check catches
+```
+
+## Empirical instances (2026-05-18, single session)
+
+### Instance 1 — P10 strict-dispatcher rule
+
+- **Rule locked** ~21:00: "P10 dispatches raw work ≥30 lines / multi-file
+  edits / `src/*.rs` to sub-agents."
+- **Skip** ~22:00: P10 authored 7 `Edit` calls directly on `adr/README.md`.
+- **Rationalization**: "adr/README.md is below threshold; not a `src/*.rs` file."
+- **Catch**: cumulative edits were dispatch-territory; user caught and flagged.
+
+### Instance 2 — Audit-mandatory rule
+
+- **Rule locked** ~22:30: "Every author dispatch pairs with independent
+  review-claude audit BEFORE merge."
+- **Skip** ~23:00: P10 dispatched ADR-0055 + ADR-0056 frame authors and
+  merged WITHOUT firing audit teammates.
+- **Rationalization**: "Frame ADRs are low-risk; no implementation surface changed."
+- **Catch**: user called this out explicitly at ~23:30.
+
+### Instance 3 — Persistent README maintenance task
+
+- **Rule locked**: README maintenance task marked "persistent" with trigger list
+  including "Phase H/I/J/K/L closure."
+- **Skip**: P10 authored ADR-0055 + ADR-0056 (Phase H + I scoping) without
+  re-triggering README maintenance.
+- **Rationalization**: "Frame ADR doesn't change public surface."
+- **Catch**: user prompted README maintenance separately.
+
+## SOP fix — three complementary enforcement levels
+
+No single fix is sufficient alone:
+
+### (a) Hard-coded process gates (strongest, highest friction)
+
+E.g. dispatch-tool auto-pairs audit-tool at call site; any `Edit` on `src/*.rs`
+triggers a dispatch-confirmation gate. Requires tooling changes.
+
+### (b) External enforcement (reliable when user is present)
+
+User catches + escalates. Effective but does not scale to overnight autonomous
+mode or high-frequency dispatch.
+
+### (c) Cadence sub-agent checkpoint (practical minimum)
+
+A review-claude dispatched at fixed cadence (e.g. end of each wave or every N
+merges) greps recent merges for:
+1. Every merge in the wave has a corresponding audit-pair PR comment or finding.
+2. Every ADR filing that matches a Phase trigger re-fired the relevant
+   persistent maintenance task.
+3. No `Edit` call on `src/*.rs` appeared in P10's direct transcript.
+
+Failure of any check → finding filed + user notified before next wave opens.
+
+### (d) Session-start checklist (near-zero cost, immediate deployable)
+
+Add a session-start checklist item: "before any Edit/dispatch, re-read the
+three rule files below." Converts passive memory into an active gate. Does
+not require tooling.
+
+**Minimum viable**: implement (d). **Preferred long-term**: implement (c) + (d).
+
+## Memory rules are not enforcement
+
+The F36 finding generalizes F1-family: F1.0-F1.5 apply to project-level rules
+and automation gaps. F36 applies to in-session agent self-discipline rules.
+Both share the root: **declaration ≠ enforcement**.
+
+A rule written in a memory file is documentation. It only fires when the agent
+actively recalls the file. An agent that has just written the rule has the
+highest confidence that the rule is loaded in-context — but also the highest
+confidence that the next case is "low-risk enough to skip." The combination
+produces systematic first-application erosion.
+
+## Cross-references
+
+- F1-family (declared rules without enforcement) — F36 is the in-session
+  agent-self-discipline instantiation.
+- F32 (PAIR pattern impl gap) — F36 is the rule-skip reason why PAIR can break
+  down even when the P10-direct pattern is available: the orchestrator skips
+  the PAIR ceremony for sprints it judges "low-risk."
+- F33 (predicate-flip cascade) — F36 explains why F33's "verify under
+  shadow-flip" gate gets skipped: agent judges the predicate "obviously
+  non-cascading."
+- Cobrust finding: `docs/agent/findings/f33-agent-self-disciplinary-rule-skip.md`
+- Cobrust memory: `feedback_post_author_audit_mandatory.md`,
+  `feedback_p10_strict_dispatcher.md`
+
+## Status
+
+Ratified 2026-05-18. Three instances in a single session satisfy the
+second-corroborator requirement. Cadence checkpoint sub-agent pattern proposed
+as minimum viable fix. Rule-skip detection added to Cobrust Tier-2 audit lanes.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F37-numeric-anchor-degradation-high-churn.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F37-numeric-anchor-degradation-high-churn.md
new file mode 100644
index 0000000..bf9f79b
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F37-numeric-anchor-degradation-high-churn.md
@@ -0,0 +1,122 @@
+---
+catalogue_id: F37
+title: "Numeric-anchor degradation in ADRs under high-churn surface files"
+family: F1-Sediment (doc-tree decay sub-family)
+severity: P2 (doc correctness)
+status: ratified_2026-05-18
+empirical_project: Cobrust v0.3.0 Phase G batch (ADR-0052a-g)
+cobrust_local_id: F34 (f34-pre-candidate-numeric-anchor-degradation-high-churn.md)
+date_ratified: 2026-05-18
+discovered_by: project-wide Tier-2 review-claude ab88ae5a4ec1ab490
+second_corroborator: Phase H batch ADRs 0055c + 0055d adopted symbol anchors explicitly
+---
+
+# F37 — Numeric-anchor degradation in ADRs under high-churn surface files
+
+## Symptoms
+
+ADRs cite `file:NNN` (file path + line number) as cross-references to source
+code locations. A few weeks later, every cited line number in those ADRs is
+wrong by 50-200+ lines. The drift is invisible: no compile error, no runtime
+failure. A reader follows the anchor and sees adjacent code that's
+plausibly-related but not the intended site — so the drift goes unnoticed until
+a dedicated anchor audit.
+
+High-churn files (compiler crates receiving frequent impl additions) exhibit
+this most severely because every sprint that adds arms or methods to existing
+functions shifts ALL downstream line numbers.
+
+## Root cause
+
+Author writes ADR at time T₀, cites `check.rs:1532` (the correct line at T₀).
+The file grows continuously as subsequent sprints add variant arms and impl
+blocks in the same file. At T₀+N days, the line cited in the ADR has drifted
+by the cumulative growth of all code added above that line. The drift is
+cumulative and monotonic during active development.
+
+F27-style "verified-at-HEAD" discipline catches drift on an INDIVIDUAL author
+dispatch — but silent drift accumulates between audits.
+
+## Quantitative evidence
+
+Cobrust Phase G batch (ADR-0052a-g), verified 2026-05-18 by project-wide Tier-2
+sweep (`ab88ae5a4ec1ab490`):
+
+- `crates/cobrust-types/src/check.rs` grew **60-80% during Phase G**
+- `crates/cobrust-cli/src/error_ux.rs` grew from ~547 to ~1194 LOC (+118%)
+
+Stale anchors found:
+- **ADR-0052b**: ~16 stale `check.rs:NNN` anchors + 6 stale `error_ux.rs:NNN`
+- **ADR-0052d-prereq**: `check.rs:920` → actual location L1008 (Δ +88 lines)
+- **ADR-0052g**: anchors pinned at `1fbed82` still valid (4-day delta only)
+- **Total**: ~24 stale anchors in 2 ADRs after ~14 days of active development
+
+## SOP fix — symbol anchors over numeric
+
+Prefer `file::symbol` over `file:NNN` for any ADR cross-reference to source
+code in actively-developed files:
+
+**Wrong (numeric anchor — drifts with file growth)**:
+```markdown
+See `crates/cobrust-types/src/check.rs:1532` — the `synth_expr` match arm
+that handles `ImplicitTruthiness`.
+```
+
+**Correct (symbol anchor — survives line-number drift)**:
+```markdown
+See `check.rs::TypeError::ImplicitTruthiness arm` in `synth_expr`.
+```
+
+or:
+
+```markdown
+See `check.rs::Ctx::synth_expr` (the `ImplicitTruthiness` match arm).
+```
+
+Symbol anchors survive line-number drift because they reference stable
+identifiers (function names, variant names, struct fields) rather than
+absolute positions. Conventional in Rust-doc culture — `rustdoc`
+cross-references are symbol-based.
+
+**High-churn file list** (as of Cobrust v0.3.0 — update for your project):
+Files receiving >10% LOC growth per sprint are high-churn. Use symbol anchors
+unconditionally for these. Numeric anchors are acceptable only for files that
+are considered stable (no active development in the current phase).
+
+**Second option — SHA-pin numeric anchors** (acceptable for point-in-time
+references):
+If a numeric anchor is load-bearing (exact line matters for the argument), pin
+it to a specific commit SHA:
+```markdown
+At `check.rs:920` (as of `1fbed82`, 2026-05-14) — note: this line drifts
+with ongoing development; prefer symbol form for long-lived references.
+```
+
+## Phase H adoption as second corroborator
+
+Phase H batch ADRs 0055c + 0055d explicitly adopted symbol-anchor convention
+throughout (e.g. `check.rs::Ctx::synth_expr`, `check.rs::Ctx::synth_call`
+over numeric `check.rs:NNN` form). Tier-1 audit `af22fcdedbd1976d5` Lane 2
+documented this adoption as a load-bearing design decision for ADR longevity.
+
+Two-phase evidence (Phase G first-instance + Phase H explicit adoption)
+satisfies the second-corroborator requirement.
+
+## Cross-references
+
+- F31 (ADR scope-reality divergence) — F37 is the doc-maintenance analog:
+  F31 catches scope gap at authorship time; F37 catches anchor gap at
+  maintenance time.
+- F36 (agent self-disciplinary rule skip) — numeric-anchor-write may itself
+  be an F36 instance: the agent knows the symbol-anchor convention but judges
+  "numeric is clearer here."
+- Cobrust finding:
+  `docs/agent/findings/f34-pre-candidate-numeric-anchor-degradation-high-churn.md`
+- Cobrust ADRs: `docs/agent/adr/0052b-*.md`, `docs/agent/adr/0055c-*.md`,
+  `docs/agent/adr/0055d-*.md`
+
+## Status
+
+Ratified 2026-05-18. Symbol-anchor convention adopted in Cobrust ADR authoring
+standard for Phase H+ batch. Existing numeric anchors remain until next Tier-2
+audit sweep (v0.4.0 ship). High-churn file list maintained in CTO runbook.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F38-test-corpus-exit-0-claim-drift.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F38-test-corpus-exit-0-claim-drift.md
new file mode 100644
index 0000000..a216c31
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F38-test-corpus-exit-0-claim-drift.md
@@ -0,0 +1,115 @@
+---
+catalogue_id: F38
+title: "TEST corpus exit-0 claim drift — TEST author's cargo check clean-claim not verifiable by DEV on post-merge crate-graph"
+family: F1-Sediment (corpus-verification sub-form)
+severity: P1 (methodology integrity)
+status: ratified_2026-05-18
+empirical_project: Cobrust v0.3.0 Phase H Wave 2 (ADR-0055b TEST corpus)
+cobrust_local_id: F35 (implicit in 0055b Tier-1 audit honesty addendum)
+date_ratified: 2026-05-18
+second_corroborator: confirmed (DEV agent 0055b found 28 hidden compile errors at TEST corpus merge SHA)
+---
+
+# F38 — TEST corpus exit-0 claim drift
+
+## Symptoms
+
+In an F32 P10-direct PAIR dispatch:
+
+1. TEST agent authors a corpus of `#[ignore]`-annotated tests, runs
+   `cargo check` (or `cargo build`) on its own branch, reports
+   `[TEST-CORPUS-READY]` with "0 compile errors."
+2. P10 reviews and dispatches DEV with TEST's commit SHA.
+3. DEV receives the corpus, attempts to un-ignore tests, and hits
+   **compile errors that were not present on TEST's branch** — typically
+   28-50 errors from API changes in a crate the TEST author compiled against
+   but is now at a different version on main after sibling merges.
+
+The TEST agent's clean-claim was correct on TEST's branch at TEST's merge time.
+It is incorrect on the post-merge crate-graph that DEV inherits. The gap is not
+TEST's fault — it is a structural verification-window problem.
+
+## Root cause
+
+TEST merges its corpus at time T₁. DEV receives the corpus at time T₂.
+Between T₁ and T₂:
+
+- Other sprints may merge changes to shared crates (e.g. a Wave-2 sibling
+  merges a `Span::new` API change from 2-arg to 3-arg).
+- The `Cargo.lock` and workspace `Cargo.toml` on main at T₂ may diverge from
+  the TEST branch's state at T₁.
+- Tests that compiled against the old API at T₁ now have 28+ compile errors
+  at T₂ against the new API.
+
+The TEST corpus's `#[ignore]` annotation is supposed to signal "do not run me
+yet" but NOT "I might not compile." DEV inherits a corpus that doesn't compile
+and cannot immediately distinguish: "the test is wrong" from "the API changed
+under me" from "the corpus never compiled even at T₁."
+
+## SOP fix — DEV must re-verify corpus on post-merge state before un-ignore
+
+Add to every DEV agent's dispatch prompt:
+
+```
+**Step 0 (mandatory, before any implementation)**:
+Run `cargo check --workspace` on the current HEAD (post-merge state).
+If compile errors appear in the TEST corpus, do NOT proceed to un-ignore.
+Instead:
+1. Record the compile errors in a §"Corpus state" section.
+2. Determine if errors are from API changes (crate diff vs. TEST branch)
+   or pre-existing test authoring bugs.
+3. Fix API-change errors (mechanical — update signatures to match current API).
+4. File a finding if errors indicate test logic bugs.
+5. Only after `cargo check` clean: proceed to un-ignore and implement.
+```
+
+This converts the "TEST corpus is ready" assumption into a verified invariant
+that DEV checks before starting work.
+
+**For TEST agents**: optionally add a `cargo check --workspace` run as the final
+step before `[TEST-CORPUS-READY]` signal, and record the SHA + toolchain version
+the check passed against. This narrows the verification window but does not
+eliminate it (merges between TEST's final check and DEV's receipt can still
+produce errors).
+
+## Evidence
+
+Cobrust ADR-0055b Phase H Wave 2, 2026-05-18:
+
+- TEST corpus merged at `2e7ccb2` (Wave 2 error.rs + lib.rs cb-mirror corpus,
+  +35 tests, all `#[ignore]`).
+- TEST merge message: "F28 strict + F34 anchors verified." Implicit in
+  "Tier-1 audit GO."
+- DEV dispatch at `84e1286` (rebase onto main after `0cfeb3f` honesty addendum).
+- DEV agent (`0055b DEV`) discovered **28 hidden compile errors** at the TEST
+  corpus merge SHA due to stale `Span::new` 2-arg API (changed to 3-arg in a
+  sibling sprint between TEST's merge and DEV's dispatch).
+- DEV corrected the 28 API-change errors mechanically, then un-ignored and
+  implemented, reaching 41/41 PASS.
+- Tier-1 audit `929cd4a` filed an honesty addendum (ADR-0055b §10.3) noting
+  the hidden compile errors as a finding.
+
+## Relationship to F32
+
+F38 is a downstream consequence of F32 (P10-direct PAIR pattern). The PAIR
+pattern correctly separates TEST and DEV to eliminate same-agent bias. F38
+shows that even with correct separation, a **temporal gap** between TEST's
+clean-compile and DEV's execution can introduce compile errors. The fix is at
+the DEV agent's Step 0, not at the PAIR separation level.
+
+## Cross-references
+
+- F32 (PAIR pattern impl gap) — F38 is the temporal-gap failure mode that
+  correct PAIR dispatch does not prevent.
+- F39 (DEV commit message scope drift) — sibling: both are DEV-agent
+  execution-time failures in the PAIR pattern.
+- Cobrust ADR: `docs/agent/adr/0055b-error-cb-mirror.md` §10.3 honesty
+  addendum (commit `0cfeb3f`)
+- Cobrust merge: `84e1286` (Wave-2 DEV rebase + 41/41 PASS)
+
+## Status
+
+Ratified 2026-05-18. DEV Step 0 verification protocol added to Cobrust DEV
+dispatch prompt template. Second corroborator: DEV agent independently
+discovered and fixed the 28 compile errors, confirming the gap is
+mechanically reproducible.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F39-dev-commit-message-scope-drift.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F39-dev-commit-message-scope-drift.md
new file mode 100644
index 0000000..9b09d77
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F39-dev-commit-message-scope-drift.md
@@ -0,0 +1,130 @@
+---
+catalogue_id: F39
+title: "DEV commit message scope drift — commit message preserves original-spec framing after mid-sprint scope reduction"
+family: F1-Sediment (commit-message surface-drift sub-form; sibling of F38)
+severity: P2 (audit/traceability integrity)
+status: ratified_2026-05-18
+empirical_project: Cobrust v0.3.0 Phase H Wave 3 (ADR-0055d commit 7100849)
+cobrust_local_id: F35-sibling-commit-msg (feedback_dev_agent_commit_msg_vs_diff_drift.md)
+date_ratified: 2026-05-18
+second_corroborator: Tier-1 audit ADR-0055d §13 amendments (`49ec536`) caught and filed
+---
+
+# F39 — DEV commit message scope drift
+
+## Symptoms
+
+A DEV agent is dispatched with an original §2 scope (e.g. "implement new Rust
+module X"). Mid-sprint, the agent correctly discovers the scope should be
+reduced (e.g. "X was already partially shipped; actual work is doc-expansion +
+test un-ignore"). The agent implements the reduced scope correctly.
+
+However, the `git commit -m` message describes the **original** scope, not the
+**final** scope. A reader of `git log` gets a false picture of what landed:
+
+- `feat(X): implement module X with 19 arms (Wave-N LARGEST DEV)` — but the
+  diff contains no Rust implementation, only pseudocode expansion + test
+  un-ignore.
+
+Future agents reading `git log` to reconstruct sprint history will believe a
+Rust module was implemented when it was not.
+
+## Root cause
+
+The DEV agent's in-context "intent" at commit time is shaped by the original
+dispatch prompt. When scope reduces mid-sprint, the original framing
+(the names, the "feat" prefix, the specific code claims) remains strongly
+activated in context. The commit message is generated from this activated
+framing, not from a fresh diff-based description.
+
+The failure has two sub-components:
+
+1. **Scope framing anchoring**: the original spec names ("cb-mirror", "19-arm",
+   "Ctx") were in the dispatch prompt, which is the longest and most
+   context-forming document in the agent's window.
+2. **Commit-message shortcut**: the agent treats the commit message as a
+   summary of "what I was working on" rather than "what I actually changed."
+
+## Rule — commit message must mirror final-form scope
+
+**Before `git commit -m`**, the DEV agent MUST answer: "Does this message
+describe what is actually in the diff, or what was in the original dispatch
+spec?"
+
+If scope changed mid-sprint:
+1. Write the commit message to describe the **final diff** (what files changed
+   and why).
+2. If the original spec framing is historically useful, add it as a
+   parenthetical or an ADR note — NOT in the `git commit -m` subject line.
+3. Use the **correct conventional-commit prefix**: `feat` implies new Rust
+   source code. `docs` + `tests` implies documentation expansion and test
+   corpus changes. Mismatched prefix is the most common symptom of scope drift.
+
+**Quick self-check before committing**:
+- Run `git diff --stat HEAD` and read the file extensions.
+- If all changed files are `.md` / `.cb` + test files with `#[ignore]` removal:
+  the prefix should be `docs`/`tests`, not `feat`.
+- If the message says "implement X" but no `.rs` impl files are in the diff:
+  the message is wrong.
+
+## Evidence
+
+Cobrust ADR-0055d Wave 3 LARGEST DEV, 2026-05-18:
+
+**Original dispatch scope**: "cb-side Rust impl mirror of `check.rs` — a
+`check_cb.rs` module with `synth_expr` 19-arm + `Ctx` struct + method-table."
+
+**Actual mid-sprint scope reduction**: Wave-3 already partially shipped scope
+was recognized; actual work reduced to:
+- 80-test `#[ignore]`-marker deletion (test un-ignore)
+- ADR ratification
+- `check.cb` doc-ref expansion (98 → 1390 lines of Cobrust pseudocode)
+
+**Committed message** (SHA `7100849`):
+```
+feat(check-cb): synth_expr 19-arm + Ctx + method-table cb-mirror (Wave-3 LARGEST DEV)
+```
+
+**What the message claims**: a new Rust `check_cb.rs` module implementing
+`synth_expr` with 19 match arms, a `Ctx` struct, and a method-table mirror.
+
+**What the diff actually contains**: `.cb` pseudocode doc-ref expansion
+(98 → 1390 lines), `#[ignore]` removal from 80 tests, ADR ratification.
+No new `check_cb.rs` Rust module; no 19-arm implementation.
+
+**Correct message** would have been:
+```
+docs(check-cb): expand check.cb doc-ref 98→1390 lines + un-ignore 80 tests (Wave-3 LARGEST DEV)
+```
+
+Tier-1 audit (ADR-0055d §13 amendments, commit `49ec536`) caught this and
+filed it as the F35-sibling finding for ADSD upstream.
+
+## Downstream consequences of F39
+
+1. Future agents reading `git log` to reconstruct sprint history believe the
+   Rust module was implemented.
+2. Tier-1 audit teammates must check the diff against the message for every
+   DEV merge — this is audit overhead that clean commit messages would eliminate.
+3. ADSD sprint accounting (which ADRs are "impl-done" vs "doc-only") is
+   corrupted, leading to duplicate dispatch risk on the next sprint.
+
+## Cross-references
+
+- F38 (TEST corpus exit-0 claim drift) — sibling failure mode in the same
+  PAIR dispatch: F38 is at TEST merge time; F39 is at DEV commit time. Both
+  produce claims about work that don't match the actual artifact.
+- F36 (agent self-disciplinary rule skip) — F39 is often an F36 instance:
+  the agent "knows" the commit message should match the diff but skips
+  the self-check because it judges the sprint "obviously correct."
+- Cobrust memory:
+  `feedback_dev_agent_commit_msg_vs_diff_drift.md`
+- Cobrust ADR: `docs/agent/adr/0055d-*.md` §13 amendments (commit `49ec536`)
+- Cobrust incident: commit `7100849` (`c89d540` in Cobrust repo — the
+  feat(check-cb) commit with scope-drifted message)
+
+## Status
+
+Ratified 2026-05-18. Diff-first commit message check added to Cobrust DEV
+dispatch prompt template. Second corroborator: Tier-1 audit teammate independently
+identified and escalated the scope-drift in the same session it was introduced.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F40-stream-watchdog-false-stall-signal.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F40-stream-watchdog-false-stall-signal.md
new file mode 100644
index 0000000..43eba1f
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/F40-stream-watchdog-false-stall-signal.md
@@ -0,0 +1,126 @@
+---
+catalogue_id: F40
+title: "Stream-watchdog false stall signal — long-running sub-agent triggers 600s timeout but ultimately completes all work post-hoc"
+family: agent-infrastructure-trust (dispatch-state verification sub-form)
+severity: P1 (dispatch economics — prevents costly duplicate work)
+status: ratified_2026-05-19
+empirical_project: Cobrust v0.3.0 Phase I wave-3 (ADR-0056c)
+cobrust_local_id: P7-stream-watchdog-false-stall (from 0056c incident 2026-05-19)
+date_ratified: 2026-05-19
+second_corroborator: confirmed (two stall signals on two agents; both subsequently completed work)
+---
+
+# F40 — Stream-watchdog false stall signal
+
+## Symptoms
+
+A sub-agent dispatch (P9 or general-purpose) is running a long-duration sprint
+(multi-crate impl + test corpus + DG verify, typically 30-90 minutes). The
+orchestrator (P10) receives a "stream idle timeout" signal or "watchdog stall"
+notification at approximately the 600-second mark.
+
+P10 dispatches a second "continuation" agent to complete the reportedly stalled
+work. Both the original agent and the continuation agent eventually signal
+completion. On inspection:
+
+- The original agent completed ALL work — multiple commits pushed to the branch.
+- The continuation agent either duplicated work or ran on a stale baseline.
+- The stall signal was **false**: the agent was alive and working throughout
+  the watchdog timeout window; it just wasn't streaming output at the
+  orchestrator's observation layer.
+
+## Root cause
+
+Long-running sub-agent phases (e.g. `cargo test --workspace` with hundreds of
+tests, DG remote compilation, LLVM/Cranelift codegen linking) do not emit
+visible output for extended periods. The orchestrator's stream-idle watchdog
+interprets silence as stall. The agent is not stalled — it is in a CPU-bound
+or IO-bound phase with no intermediate stdout to emit.
+
+Two contributing factors:
+
+1. **Watchdog fires on stdout silence**, not on process liveness. A 10-minute
+   `cargo test` run with no output is indistinguishable from a hung process at
+   the stream layer.
+2. **Orchestrator response to stall is dispatch-based** (send another agent)
+   rather than verify-based (check branch state before acting). The dispatch-based
+   response transforms a false positive into an expensive double-dispatch.
+
+## SOP fix — verify-before-act protocol
+
+**When a watchdog stall signal fires on a sub-agent dispatch**:
+
+1. **STOP. Do NOT immediately dispatch a continuation agent.**
+2. **Check branch state** (3 commands, 30 seconds):
+   ```bash
+   # Check if the agent pushed any commits
+   git log --oneline origin/<branch-name> | head -5
+   # Check if DG run logs show completion
+   ls -lt /tmp/cobrust-*/  # or equivalent DG output directory
+   # Check if the workspace compiles
+   cargo check --workspace 2>&1 | tail -5
+   ```
+3. **Interpret the evidence**:
+   - Branch has new commits → agent completed work, stall was false positive.
+     Review the commits; decide if more work is needed.
+   - Branch has no commits but workspace compiles → agent may have been mid-impl;
+     check DG run status before deciding.
+   - Branch has no commits and workspace errors → agent likely stalled before
+     completing; dispatch continuation.
+4. **Only after Step 3**: dispatch continuation if evidence shows genuine stall.
+
+## Evidence
+
+Cobrust ADR-0056c Phase I wave-3 (fn-redef), 2026-05-19:
+
+- **Agent `a2b6ebf2995b88d08`** dispatched for Phase I wave-3 fn-redef impl.
+  Stream-watchdog stall signal at ~600s.
+- **Agent `aab5aaafa919c0ff3`** dispatched as continuation. Also reported stall.
+- **Post-hoc inspection**: original agent `a2b6ebf2995b88d08` eventually pushed
+  **6 commits** to `feature/0056c-fn-redef`:
+  - `8e28b7f` feat(types): TypeCheckCtx::invalidate_def per-symbol API
+  - `1f0f4b3` feat(session): Session::redefine_fn atomic re-bind + REPL UX
+  - `9bdf48f` tests(session): fn-redef contract (8 tests, 0056c)
+  - `fd4de42` tests(0056c): DG verify fn-redef 8/8 PASS, 0 regression
+  - `3626021` docs: Phase I wave-3 fn-redef dual-track (zh + en + agent)
+  - `2ae8c52` docs(adr): 0056c ratify accepted
+- All 6 commits were post-stall-signal. The agent completed full work including
+  DG verify after the watchdog fired.
+- The continuation agent `aab5aaafa919c0ff3` ran on a stale baseline — its
+  work was redundant and was discarded.
+
+## Cost of false positive without this SOP
+
+- **Wasted continuation dispatch**: ~30-60 min of agent time on redundant work.
+- **Merge confusion**: two branches with overlapping work require manual
+  resolution.
+- **Context burn**: P10 spends context budget managing a "stall recovery" that
+  wasn't needed.
+
+## Complementary tool: check-before-act on all signal types
+
+The verify-before-act protocol generalizes: for ANY "something may have gone
+wrong" signal (stall, timeout, error message, unexpected silence), check the
+artifact state (branch commits, build output, test results) before re-dispatching.
+
+Most "failures" in long-running agent infrastructure are latency mismatches
+between agent execution time and orchestrator observation cadence, not genuine
+stalls.
+
+## Cross-references
+
+- F36 (agent self-disciplinary rule skip) — F40 is the infrastructure-level
+  analogue: the agent (orchestrator) skips the verify step because dispatching
+  "feels right" when a stall signal appears.
+- `feedback_p9_two_phase_dispatch.md` (Cobrust CTO runbook) — two-phase
+  dispatch SOP for genuine stalls (spike-commit + respawn); F40 is the
+  pre-condition check that determines whether two-phase dispatch is needed.
+- Cobrust commits: `8e28b7f`, `1f0f4b3`, `9bdf48f`, `fd4de42`, `3626021`,
+  `2ae8c52` (all pushed post-stall by agent `a2b6ebf2995b88d08`)
+- Cobrust merge: `663cd56` (Phase I wave-3 fn-redef full close)
+
+## Status
+
+Ratified 2026-05-19. Verify-before-act protocol added to Cobrust CTO runbook
+§"Watchdog stall response." Two independent stall signals on two agents, both
+eventually completing work, satisfies second-corroborator requirement.
diff --git a/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/README.md b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/README.md
new file mode 100644
index 0000000..a9fa45f
--- /dev/null
+++ b/plugins/adsd/skills/agent-driven-development/reference/cobrust-f31-f39/README.md
@@ -0,0 +1,58 @@
+---
+doc_kind: batch-index
+batch_id: cobrust-f31-f39
+title: "F31-F40 — Cobrust v0.3.0 empirical corroboration batch"
+date: 2026-05-19
+cobrust_version: v0.3.0
+sprint_range: "Phase F.3 Wave 1 (2026-05-16) → Phase I Wave 3 (2026-05-19)"
+total_findings: 10
+---
+
+# F31–F40 Cobrust empirical corroboration batch
+
+Ten failure-mode findings empirically corroborated by the **Cobrust v0.3.0**
+sprint cadence (Phase F.3 → Phase I, 2026-05-16 to 2026-05-19).
+
+Each finding satisfies the catalogue's second-corroborator requirement: the
+entry records the specific Cobrust SHA(s) where the pattern was observed plus
+the independent audit or dispatch that confirmed it.
+
+## Index
+
+| File | Catalogue ID | One-line summary |
+|---|---|---|
+| F31-adr-scope-reality-divergence.md | F31 | ADR batch frame over-scopes without source-code verification gate |
+| F32-pair-pattern-impl-gap-single-layer-subagent.md | F32 | PAIR ceremony unimplementable on single-layer agent platforms |
+| F33-predicate-flip-cascade-discovery-deficit.md | F33 | F29 enumeration misses latent consumers of flipped predicates |
+| F34-wrapper-type-bidirectional-unify-ambiguous-type-cascade.md | F34 | Bidirectional `Ref(T) ↔ T` unify produces 142-failure cascade |
+| F35-wave2-cascade-discovery-deficit-third-instance.md | F35 | Third corroboration: ADR forward-looking claim ≠ current source state |
+| F36-agent-self-disciplinary-rule-skip.md | F36 | Agent skips rules it just wrote when judged "low-risk" |
+| F37-numeric-anchor-degradation-high-churn.md | F37 | `file:NNN` anchors drift >100 lines in 14 days on high-churn files |
+| F38-test-corpus-exit-0-claim-drift.md | F38 | TEST corpus clean-claim invalid on post-merge crate-graph at DEV time |
+| F39-dev-commit-message-scope-drift.md | F39 | DEV commit message preserves original-spec framing after scope reduction |
+| F40-stream-watchdog-false-stall-signal.md | F40 | 600s watchdog signal is false-positive; agent completes work post-hoc |
+
+## Cobrust SHA index
+
+Key SHA anchors cited across findings (all on `Cobrust-lang/Cobrust` repo, branch `main`):
+
+| SHA | Role |
+|---|---|
+| `891d235` | ADR-0050 batch frame at F31's over-scope moment |
+| `30cf2b2` | HEAD at F31 pre-impl audit (3/5 features already shipped) |
+| `1998dbe` | P9-A spike (independent F31 rediscovery — break/continue) |
+| `909811f` | P9-B spike (independent F31 rediscovery — for-loop) |
+| `aca5d87` | Wave 2 cascade fix merge (F33 latent consumers) |
+| `23cadf6` | ADR-0052a pre-revision (bidirectional unify design, F34) |
+| `bcf9c7d` | ADR-0052a revised (one-way coercion design replacing F34 trigger) |
+| `6843a33` | DEV v3 merge (F34 — 0 regressions after design fix) |
+| `1643776` | 0052d-prereq-dev HEAD (F35 parser blocker verified) |
+| `0f42be2` | TEST corpus merge (F38 — TEST clean-claim baseline) |
+| `2e7ccb2` | Wave-2 TEST final merge on main (F38 crate-graph state) |
+| `84e1286` | DEV 0055b rebase + 41/41 PASS (F38 DEV-verified clean) |
+| `0cfeb3f` | Tier-1 honesty addendum (F38 28 hidden errors documented) |
+| `7100849` / `c89d540` | F39 scope-drifted commit (feat ≠ diff) |
+| `49ec536` | Tier-1 amendments catching F39 |
+| `56c81bb` | ADR-0055d merge (F39 filed as F35-sibling finding) |
+| `8e28b7f` | F40 — first post-stall commit from agent `a2b6ebf` |
+| `663cd56` | ADR-0056c final merge (F40 — all work completed post-hoc) |