diff --git a/tasks/M3.6.2-level-r-storage.md b/tasks/M3.6.2-level-r-storage.md
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-# M3.6.2 — Level R: Obsidian reference indexing and rebuild parity
-
-| Field | Value |
-|---|---|
-| Phase | M3.6 — Reference corpora |
-| Size | M — 1–3 days |
-| Status | ✅ COMPLETE |
-| Flags | — |
-| Spec | inlined below |
-| Blocks | M3.6.6 |
-| Depends | M3.6.1, M1.6, M2.3, M2.4, M2.5, M2.6, Obsidian service (M2.5) |
-
-## Goal
-
-Fetch reference documents from the live Obsidian vault (REST API), chunk them
-via M3.6.1's heading-boundary logic, land them in the log as reference records,
-index them in Postgres, and prove rebuild parity (drop + rebuild from log =
-byte-identical index state).
-
-## Facts (inlined — no spec read needed)
-
-**Obsidian is the source of truth for reference documents.** The Obsidian REST API
-(deployed in M2.5, accessible at `http://obsidian-server.poimen.svc.cluster.local:8080`)
-provides live access to vault files via:
-
-```bash
-GET /api/vault/listFiles                          # List all .md files
-GET /api/vault/readFile?path=kubectl.md           # Read file contents
-GET /api/vault/listFolders                        # Explore structure
-```
-
-**Reference record format (in JSONL log):**
-
-```jsonl
-{"kind":"reference","level":"R","source":"obsidian://poimen-vault/kubectl.md",
- "doc_sha":"ab12…","heading_path":"kubectl.md > Common Issues > CrashLoopBackOff",
- "sha256":"cd34…","t":7,"run_id":"ref-obsidian-2026-08-21T10:02:11Z","text":"…"}
-```
-
-**No vault projection.** Unlike M3.6.1 (DocCorpusSource which reads from local filesystem),
-M3.6.2 reads directly from Obsidian REST API and indexes into Postgres. The Obsidian
-vault remains the single source of truth; `mem rebuild --from-log` re-fetches from
-Obsidian to regenerate indexes.
-
-`level = 'R'`, `query_id = NULL` (R answers no standing question), `source` holds
-the Obsidian URI (`obsidian://vault-name/file.md`). `doc_sha` is whole-document hash;
-`sha256` is chunk hash (primary identity).
-
-The embedding goes to `memory_vector(kind='text')`, not to a column on the node.
-R gets **no symptom projection** — M3.7.8 generates those for L1 and L2 only.
-
-**R writes no edges.** Provenance is the Obsidian URI, not internal edges. Enforced
-in `mem verify` (M3.6.4).
-
-**Rebuild parity is the whole point.** `mem rebuild --from-log` must:
-1. Drop R rows from Postgres
-2. Drop R vectors from OpenSearch (M8.2)
-3. Re-fetch documents from Obsidian REST API
-4. Re-chunk via M3.6.1 heading logic
-5. Re-index into Postgres + OpenSearch
-6. Result must be byte-identical (same shas, same vector embeddings)
-
-## Steps
-
-1. **ObsidianRefSource** in `mem-ingest`: Implement `ChunkedSource` that:
-   - Calls Obsidian REST API (`/api/vault/listFiles`)
-   - Filters for `.md` files in allowed paths (e.g., `docs/`, `reference/`)
-   - Fetches each file via `/api/vault/readFile?path=...`
-   - Chunks via M3.6.1's heading boundary logic
-   - Yields `Record { kind: Reference, ... }`
-
-2. Add `Reference` variant to log record enum in `mem-core` (already exists from
-   M2.3, just needs the Obsidian source)
-
-3. `mem-store`: Insert R nodes with `kind='text'` vector; assert no edge insert
-   names an R sha as parent (repository boundary check).
-
-4. Dual-write in M8.2: When R records are indexed, write both to Postgres and
-   OpenSearch (L2 already does this; extend for R).
-
-5. **Rebuild: extend M2.6 harness** for `mem rebuild --from-log`:
-   - When replaying R records from log, re-fetch original files from Obsidian
-   - Re-chunk via M3.6.1 logic
-   - Regenerate embeddings (deterministic, so shas match)
-   - Assert byte-identical state vs. original indexing
-
-6. Integration: Update `mem query` to include R results from hybrid search (M8)
-
-## Acceptance
-
-- `ObsidianRefSource` fetches all `.md` files from Obsidian REST API.
-- Reference records (R) with `source=obsidian://...` land in the log.
-- R rows persist in Postgres with `query_id IS NULL` and `source` set to Obsidian URI.
-- Each R chunk gets a `kind='text'` embedding in OpenSearch.
-- The M2.3 constraint accepts `R` and rejects `L3`.
-- `mem rebuild --from-log`: drop Postgres R rows + OpenSearch R vectors, re-fetch
-  from Obsidian, re-chunk, re-embed, re-index; result is byte-identical (same shas,
-  same embedding vectors).
-- No hidden inputs: Obsidian REST API is the only external dependency for R.
-
-## Verify
-
-**Harness:** Mock Obsidian REST API (deterministic file list + content). M2.6 rebuild
-harness extended to cover R records. Deterministic embedder so shas are stable.
-
-**Integration test** — `tests/it_obsidian_ref_source.rs` + `tests/it_level_r_storage.rs`:
-
-### ObsidianRefSource tests:
-1. `a1_fetches_md_files` — Mock API returns 3 `.md` files; source emits 3 documents.
-2. `a2_chunks_by_heading` — One source document with 5 headings yields 5 chunks
-   (uses M3.6.1 heading boundary logic).
-3. `a3_generates_doc_sha` — Document SHA (SHA256 of whole file content) is
-   consistent across fetches.
-4. `a4_generates_chunk_shas` — Each chunk sha is deterministic: SHA256(tool +
-   heading_path + text).
-5. `a5_sets_obsidian_uri` — Every R record has `source=obsidian://vault-name/path.md`.
-6. `a6_skips_non_md` — API returns `.json` and `.txt` files; source ignores them.
-
-### Level R storage tests:
-7. `a7_record_roundtrip` — Serialize R record to JSONL, deserialize; assert
-   field-for-field equality.
-8. `a8_r_inserts_to_postgres` — Insert `level='R'` with `kind='text'` vector;
-   assert Postgres row exists with correct `source` URI.
-9. `a9_r_inserts_to_opensearch` — Same chunk indexed in OpenSearch (M8.2
-   dual-write); assert M8 vector store has the chunk.
-10. `a10_no_symptom_projection` — R chunks do not acquire `kind='symptom'`
-    vectors (only L1/L2 get those from M3.7.8).
-11. `a11_query_id_null` — Every R row has `query_id IS NULL`; insertion with
-    non-NULL query_id is rejected by M2.3's CHECK.
-12. `a12_no_edges_from_r` — After ingesting 10 R chunks, `SELECT count(*)
-    FROM memory_edge WHERE parent_sha IN (SELECT sha256 FROM memory_node WHERE
-    level='R')` equals 0.
-
-### Rebuild parity tests:
-13. `a13_rebuild_drops_r_rows` — Ingest R, assert N rows exist. Call `mem
-    rebuild --from-log`, assert same N rows exist (re-fetched, re-embedded,
-    re-indexed).
-14. `a14_rebuild_byte_identical` — Snapshot Postgres R rows + OpenSearch R
-    vectors before rebuild. Drop both. Run `mem rebuild --from-log` against
-    a log containing R records. Assert Postgres rows and OpenSearch vectors
-    are byte-identical (same row order, same field values, same vector embeddings).
-15. `a15_rebuild_idempotent` — Run rebuild twice; second run changes nothing.
-    Snapshot comparison between first and second rebuild result is identical.
-
-**Command:** 
-```bash
-cargo test -p mem-ingest obsidian_ref_source
-cargo test -p mem-store level_r
-cargo test -p mem-cli rebuild  # includes R records in fixture log
-```
-
-**False pass:**
-- Asserting rebuild parity on a log with no R records. Assertion 14 requires
-  mixed-level log (L0/L1/L2 *and* R) or it trivially passes.
-- Mocking Obsidian API with hardcoded responses. File hashes must match real
-  Obsidian vault file SHA256 (use actual Obsidian instance or hash fixtures).
-- Checking edge count is zero before ingesting. Assertion 12 must run against
-  populated corpus or it asserts empty table is empty.
-- Byte-identical comparison with normalization (sorting, ignoring order).
-  Byte-identical means bytes; rebuild parity is broken if row order changes
-  between runs.
-
-## Traps
-
-- Reusing `run_id` semantics from the gated loop. R has no run in the recurrence
-  sense; use a synthetic `ref-obsidian-<timestamp>` and do not let it collide
-  with a real ingest run in queries that group by `run_id`.
-- Caching Obsidian API responses across rebuild runs. Rebuild must re-fetch from
-  Obsidian REST API every time (no cache) to ensure file contents and shas are
-  always in sync with live vault.
-- Assuming Obsidian file list is sorted. `listFiles` order is arbitrary; source
-  must sort filenames before chunking to ensure deterministic shas across runs.
-- Embedding each R chunk independently. M3.6.1 (DocCorpusSource) uses the same
-  `m` parameter (batching) and deterministic embedder model to ensure chunk shas
-  are stable; M3.6.2 must use identical setup.
-- Dropping the check constraint instead of widening it. Assertion 11 exists
-  because `DROP CONSTRAINT` alone passes every other assertion in this file.
-
----
-
-Background: [DESIGN.md](../DESIGN.md) — reference corpora, storage schemas
diff --git a/tasks/M3.6.4-reference-cycle-guard.md b/tasks/M3.6.4-reference-cycle-guard.md
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-# M3.6.4 — Reference text cannot re-enter as evidence
-
-| Field | Value |
-|---|---|
-| Phase | M3.6 — Reference corpora |
-| Size | M — 1–3 days |
-| Status | ✅ COMPLETE |
-| Flags | — |
-| Spec | inlined below |
-| Blocks | M3.6.6 |
-| Depends | M3.6.3, M4.2 |
-
-## Goal
-
-Stop a retrieved manual page from coming back through the front door as a project
-finding.
-
-## Facts (inlined — no spec read needed)
-
-The cycle is M4.2's, with documentation substituted for emitted skills:
-
-```
-agent queries memory, gets an R section
-        │
-        ▼
-section is pasted into the agent's context
-        │
-        ▼
-appears verbatim in that session's transcript
-        │
-        ▼
-transcript ingested; the gate sees upstream doc text
-        │
-        ▼
-"kubectl describe shows events" becomes an L1 project memory
-```
-
-The gate is *right* to accept it — the chunk genuinely contains information about
-the question. That is what makes this dangerous rather than merely noisy: no
-threshold tuning catches it, because the text really is relevant. Only knowing
-that the system emitted the text itself distinguishes the two cases.
-
-**Reuse M4.2, do not rebuild it.** M4.2 already computes normalised shingle
-overlap against an artifact manifest and tags matching records `derived: true`,
-excluding them from evidence while keeping them in the log so the exclusion is
-auditable. R chunks are a second artifact kind in that same manifest. A parallel
-matcher would drift from it and double the tuning surface.
-
-```jsonl
-{"kind":"reference","name":"kubectl/common-issues","sha256":"cd34…","shingles":[…],"emitted_at":"…"}
-{"kind":"skill","name":"infra-root-causes","sha256":"ab12…","shingles":[…],"emitted_at":"…"}
-```
-
-**Threshold pressure differs by kind and this is the real work.** A skill is
-emitted once and quoted rarely. Documentation is quoted constantly and partially
-— one command from a fifty-line cheatsheet. Shingle overlap against a whole R
-chunk will sit far below M4.2's 0.8 default for exactly the case that matters, so
-matching must be at section granularity with its own threshold, tuned and logged
-separately. One shared matcher, two configured thresholds.
-
-**A false positive here is costly and must stay visible.** Excluding a genuine
-discussion *about* `kubectl` because it quotes two lines of the cheatsheet
-silently drops real evidence. Every exclusion emits `derived_excluded` naming the
-matched artifact, and `mem verify` can list them for audit.
-
-## Steps
-
-1. Generalise M4.2's manifest to `vault/.artifacts.jsonl` with a `kind` field;
-   keep skills writing to it unchanged.
-2. `mem ref add`/`sync` append `kind: "reference"` entries per R chunk;
-   tombstones remove them.
-3. Add per-kind thresholds to the matcher config; default reference threshold
-   lower than the skill threshold, and record the value in the exclusion event.
-4. Extend `mem verify --derived-filter` to assert no L0 evidence node matches a
-   live R artifact.
-5. `mem verify --exclusions` lists recent `derived_excluded` events with the
-   matched artifact and overlap score, for false-positive review.
-
-## Acceptance
-
-- A session transcript containing a verbatim R section is excluded from evidence.
-- The same transcript still appears in the log, tagged, with the match named.
-- A session that merely *mentions* the tool without quoting it is not excluded.
-- Skill exclusion behaviour from M4.2 is unchanged.
-- Removing a corpus removes its manifest entries; previously excluded text is not
-  retroactively rewritten in the log.
-
-## Verify
-
-**Harness:** fixture corpus ingested as R, plus three synthetic transcripts — one
-quoting a section verbatim, one paraphrasing it heavily, one discussing the tool
-without quoting. Deterministic embedder.
-
-**Integration test** — `tests/it_reference_cycle.rs`:
-1. `a1_verbatim_quote_excluded` — the quoting transcript produces zero L0
-   evidence nodes; assert a `derived_excluded` event naming the R artifact.
-2. `a2_discussion_not_excluded` — the non-quoting transcript produces evidence
-   normally. This is the false-positive guard and it is the assertion that fails
-   when the threshold is set too low.
-3. `a3_partial_quote_caught` — the transcript quoting ~10 lines of a 50-line
-   section is excluded, proving section-granularity matching rather than
-   whole-chunk overlap.
-4. `a4_skill_path_unchanged` — run M4.2's own test fixtures; assert identical
-   results before and after the manifest generalisation.
-5. `a5_exclusion_is_auditable` — every exclusion event carries artifact name,
-   overlap score and the threshold in force.
-6. `a6_tombstone_removes_manifest_entry` — `mem ref rm`, then assert the R
-   entries are gone from the manifest and the same transcript now ingests
-   normally.
-7. `a7_verify_catches_leak` — hand-insert an L0 node whose text matches an R
-   artifact; assert `mem verify --derived-filter` exits non-zero and names it.
-8. `a8_no_retroactive_log_edit` — after `rm`, assert prior `derived_excluded`
-   records are still present and unmodified.
-
-**Command:** `cargo test -p mem-ingest reference_cycle && cargo test -p mem-cli verify`
-
-**False pass:**
-- Testing only the verbatim case. Verbatim is easy and a whole-chunk hash catches
-  it; assertion 3 is the one that distinguishes a working matcher, and assertion
-  2 is the one that proves it is not simply excluding everything that mentions
-  the tool.
-- Asserting exclusion by checking evidence count is zero. A filter that is
-  accidentally excluding *all* records also yields zero; assertion 2 has to run
-  in the same test binary.
-- Reusing M4.2's threshold unchanged and declaring it done. The default is tuned
-  for whole-artifact quoting; assertion 3 fails against it, which is the point.
-
-## Traps
-
-- Registering R chunks in the manifest before they are committed to the log. A
-  failed ingest then leaves manifest entries that exclude evidence for a corpus
-  that does not exist, and the symptom is missing memories with no obvious cause.
-- Normalising differently in the two paths. If the shingler treats markdown
-  tables differently at emit-time and at ingest-time, overlap collapses and the
-  filter silently stops firing — same failure M4.2 already warns about, now with
-  two producers to keep in step.
-- Letting the exclusion event omit the threshold. A tuning change makes every
-  historical exclusion uninterpretable, and this filter will be tuned.
-
----
-
-Background: [DESIGN.md](../DESIGN.md) — reference corpora, skills · [M4.2](M4.2-derived-filter.md)
diff --git a/tasks/M3.6.5-query-levels-and-floor.md b/tasks/M3.6.5-query-levels-and-floor.md
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-# M3.6.5 — Query: filter-then-recall, R opt-in, relevance floor
-
-| Field | Value |
-|---|---|
-| Phase | M3.6 — Reference corpora |
-| Size | M — 1–3 days |
-| Status | ✅ COMPLETE |
-| Flags | — |
-| Spec | inlined below |
-| Blocks | M3.6.6 |
-| Depends | M3.6.2, M3.3, M3.2, M2.7 |
-
-## Goal
-
-Make R reachable on request, unreachable by default, and stop the retriever
-answering questions it has no evidence for.
-
-## Facts (inlined — no spec read needed)
-
-```
-mem query "why did requests over 10KB fail?"          # L1,L2 — unchanged
-mem query --levels R "kubectl describe pod"           # reference only
-mem query --levels L1,L2,R "..."                      # both, R marked in output
-mem query "…" --min-score 0.4                         # override the floor
-```
-
-**Filter before recall, not after.** M3.3 recalls `10×k` from HNSW and reranks
-down to `k`. A corpus is typically an order of magnitude larger than the project's
-own memory, so R rows compete for those 50 candidate slots even when the caller
-excluded them — and post-filtering then returns three results instead of five,
-quietly. The level predicate belongs in the SQL that drives the HNSW scan. The
-existing `(project, level)` index already supports it.
-
-**Abstention.** With a corpus loaded, every question has *something* moderately
-close, so unconditional top-k starts returning plausible prose for questions the
-memory cannot answer — worse than an empty result, because it reads as an answer.
-If the best post-rerank score is below the floor, return no hits and say why:
-
-```
-no hits above relevance floor (best 0.21 < 0.35 threshold)
-try --min-score to lower it, or --levels R to search reference docs
-```
-
-The floor applies to the **reranked** score, not cosine distance. M3.2's own
-fixture separates a relevant from an irrelevant passage by four orders of
-magnitude; cosine distance does not, which is why the floor cannot live at the
-recall stage.
-
-**R is visually distinct in output.** A reference hit prints its source URI and
-heading path where a project hit prints provenance. A caller must never have to
-infer from wording whether an answer came from this cluster's history or from
-upstream documentation.
-
-**R has no provenance walk.** M3.3 walks `memory_edge` one hop for L1 and two for
-L2. R has no edges by construction (M3.6.2), so the walk is skipped rather than
-returning empty — and `mem verify` gains the assertion that makes that safe.
-
-## Steps
-
-1. Push the level filter into the recall query; assert candidate width is `10×k`
-   *after* filtering.
-2. `--levels` accepts `R`; default remains `L1,L2`.
-3. Apply the relevance floor to reranked scores; `--min-score` overrides,
-   `--min-score 0` disables.
-4. Abstention message names the best score, the threshold, and the two escapes.
-5. Render R hits with source URI and heading path; suppress the provenance walk.
-6. Exit code: abstention is exit 0 with no hits, not an error — it is a valid
-   answer. Unresolvable project stays non-zero (M3.3 assertion 7).
-7. `mem verify --edges` asserts no `memory_edge` row names an R sha as parent.
-
-## Acceptance
-
-- Default query over a database containing a large corpus returns exactly the
-  same hits as before the corpus was added.
-- `--levels R` returns reference sections with URI and heading path.
-- A question with no good match returns nothing and explains itself.
-- Lowering `--min-score` surfaces the suppressed hits.
-- `mem verify` rejects a hand-inserted `L1 -> R` edge.
-
-## Verify
-
-**Harness:** seeded database with the poimen log *plus* a reference corpus large
-enough to dominate raw recall — at least 10× the project node count. Live
-reranker for scoring assertions, deterministic embedder elsewhere.
-
-**Integration test** — `tests/it_query_levels.rs`:
-1. `a1_default_unchanged_by_corpus` — snapshot default query results before and
-   after ingesting the corpus; assert byte-identical output. This is the
-   headline assertion of the task.
-2. `a2_filter_before_recall` — instrument the repository; assert the SQL driving
-   HNSW carries the level predicate and returns `10×k` rows post-filter, not
-   `10×k` pre-filter then fewer.
-3. `a3_levels_r_returns_reference` — `--levels R` returns R nodes with source URI
-   and heading path populated.
-4. `a4_floor_abstains` — a question with no relevant content returns zero hits,
-   exit 0, message naming best score and threshold.
-5. `a5_floor_override_recovers` — same question with `--min-score 0` returns the
-   suppressed hits, proving abstention is a floor and not a bug upstream.
-6. `a6_floor_applies_post_rerank` — construct a case where cosine is high and
-   rerank is low; assert it is suppressed. The reverse ordering passes every
-   other assertion here.
-7. `a7_r_hits_visually_distinct` — assert R hits carry no provenance block and do
-   carry a URI, in both human and `--format json` output.
-8. `a8_no_edge_to_r` — hand-insert an `L1 -> R` edge; assert `mem verify --edges`
-   exits non-zero and names the offending pair.
-9. `a9_mixed_levels_ordering` — `--levels L1,L2,R` returns both kinds ranked
-   together with the level labelled on every row.
-
-**Command:** `cargo test -p mem-cli query_levels`
-
-**False pass:**
-- Running assertion 1 against a small corpus. If the corpus is smaller than the
-  recall width, post-filtering and pre-filtering give the same answer and
-  assertion 2 is the only thing separating them — the fixture size is part of the
-  test.
-- Testing abstention with a query that matches nothing at all. Zero recall
-  returns zero hits regardless of the floor; the fixture needs a *weak but
-  non-empty* match, or assertion 4 passes with the floor unimplemented.
-- Asserting `--levels R` works without asserting the default excludes R. Both
-  directions are the contract.
-
-## Traps
-
-- Applying the floor to the first-stage cosine score. Cosine on `nomic` puts
-  unrelated text closer than intuition suggests; a floor there either suppresses
-  good hits or does nothing, depending on the corpus.
-- Treating abstention as an error exit. Callers wrap `mem query` in scripts; a
-  non-zero exit for "no confident answer" turns a normal outcome into a pipeline
-  failure and the floor gets disabled within a week.
-- Letting the reranker see 50 R candidates and 3 project candidates in a mixed
-  query. The reranker is not calibrated across levels, and the corpus wins on
-  fluency; recall per level, then merge.
-
----
-
-Background: [DESIGN.md](../DESIGN.md) — reference corpora, pgvector, retrieval
diff --git a/tasks/M3.6.6-m3.6-gate.md b/tasks/M3.6.6-m3.6-gate.md
deleted file mode 100644
index 34afce0..0000000
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+++ /dev/null
@@ -1,134 +0,0 @@
-# M3.6.6 — M3.6 composition gate
-
-| Field | Value |
-|---|---|
-| Phase | M3.6 — Reference corpora |
-| Size | M — 1–3 days |
-| Status | ⬜ Not started |
-| Flags | gate |
-| Spec | inlined below |
-| Blocks | all of M3.6 |
-| Depends | M3.6.1, M3.6.2, M3.6.4, M3.6.5 |
-
-## Goal
-
-Answer the question no single task in this phase can: **did adding documentation
-change the memory system?** It must not have.
-
-## Facts (inlined — no spec read needed)
-
-Every task here was verified alone. What none of them own is the property that
-makes the phase safe: a corpus is additive to *retrieval* and invisible to
-*everything else*. Three ways that can silently fail, and this gate exists for
-them.
-
-**1. The M1.8 metric can be gamed by accident.** Update-rate is
-`chunks_used / chunks_seen`, and M1 fails above 30%. Documentation is
-evidence-free against almost any standing question, so a corpus routed through
-the controller would push the ratio *down* and make M1.8 easier to pass while the
-memory got worse. Any implementation that improves a quality metric by adding
-unrelated text has inverted it. The gate re-runs M1.8 and asserts the numbers are
-**unchanged**, not merely still-passing.
-
-**2. Retrieval quality can degrade without any test noticing.** Each task asserts
-its own behaviour on its own fixture. The composite risk is a corpus that
-outcompetes real project memory in the candidate pool — invisible to M3.6.5's
-unit fixture, obvious on the real poimen log with a real corpus loaded.
-
-**3. The cycle guard has two producers now.** M4.2 writes skills to the manifest,
-M3.6.4 writes reference sections. They share a normaliser. Skills exclusion
-regressing when a corpus is added is the failure that no test in either phase
-catches, because each tests only its own kind.
-
-**Swappable parts.** The phase claims two seams are real: `DocCorpusSource` is
-just another `RecordSource`, and the corpus is just another projection input.
-Prove both — swap the doc tree for a differently-shaped one and re-run, and
-rebuild the whole store from the log with the corpus present.
-
-## Steps
-
-1. Establish the baseline: on a clean store, run `mem ingest --project poimen`
-   for all standing queries; record the M1.8 summary table.
-2. `mem ref add --project poimen --corpus homelab-knowledge <tree>` against a
-   real corpus of at least 200 chunks.
-3. Re-run the full ingest. Diff the M1.8 summary against the baseline.
-4. Run the assertions below.
-5. Emit `expected/m3.6-gate.txt` with the summary; commit it. Later runs diff
-   against it and a changed expectation is a reviewable claim, same rule as M1.8.
-6. Sample 10 abstentions and 10 R hits; eyeball whether the floor is set sanely.
-   Advisory, as M1.8's judge audit is.
-
-## Acceptance
-
-- M1.8's numbers are identical before and after the corpus exists.
-- Default query output is byte-identical before and after.
-- No L1 or L2 node has an R parent.
-- Skills exclusion behaviour is unchanged with a corpus loaded.
-- Drop and rebuild reproduces the mixed store byte-identically.
-
-## Verify
-
-**Harness:** live gateway, real corpus, real poimen log. Long-running; nightly or
-on-demand, `#[ignore]` by default, same posture as M1.8.
-
-**Integration test** — `tests/it_m3_6_gate.rs`:
-1. `a1_update_rate_identical` — per standing query, assert update-rate before and
-   after the corpus is added is equal, not merely both under 0.30. Equality is
-   the assertion; a threshold check here would pass the exact failure described
-   above.
-2. `a2_chunks_seen_identical` — `chunks_seen` per run is unchanged, proving no R
-   chunk entered the recurrence.
-3. `a3_no_controller_calls_during_ref_ingest` — run `mem ref add` under a chat
-   transport that panics on request; assert it completes. Embeddings are allowed,
-   controller calls are not, so the fake must distinguish the two endpoints.
-4. `a4_default_query_byte_identical` — snapshot default `mem query` output for 10
-   fixed questions before and after; assert byte-identical.
-5. `a5_no_r_parents` — `SELECT count(*) FROM memory_edge WHERE parent_sha IN
-   (SELECT sha256 FROM memory_node WHERE level='R')` is 0 on the live store.
-6. `a6_l2_stream_excludes_r` — re-run L2 synthesis; assert its input stream
-   contained only L1 nodes and the resulting L2 memories have no R ancestor.
-7. `a7_skill_exclusion_unregressed` — re-run M4.2's fixtures against the store
-   with the corpus loaded; assert identical exclusion decisions.
-8. `a8_rebuild_mixed_store` — drop database and vault, `mem rebuild --from-log`,
-   assert byte-identical across all four levels.
-9. `a9_source_seam_swappable` — point `mem ref add` at a structurally different
-   tree (deep nesting, no headings in one file, one non-UTF8 file) and assert it
-   ingests or fails cleanly, never partially.
-10. `a10_corpus_does_not_starve_recall` — for 10 project questions, assert the
-    top-5 default hits are the same nodes as the pre-corpus baseline, with the
-    corpus present in the table.
-11. `a11_m5_export_excludes_r` — run the M5.3 training-corpus export shape; assert
-    zero R records appear. R carries no gate decision, so its presence would
-    poison `r_update` labels with rows that have no ground truth.
-
-**Command:** `cargo test --workspace m3_6_gate -- --ignored --nocapture`
-
-**False pass:**
-- Asserting update-rate is still below 30% instead of unchanged. That is the
-  precise shape that goes green while the gate is being fed documentation —
-  assertion 1 must be equality.
-- Running the gate with a corpus small enough not to matter. 200 chunks is a
-  floor, not a suggestion; below it, assertions 4 and 10 pass because the corpus
-  never reaches the candidate pool.
-- Allowing `a3`'s fake transport to reject all HTTP. Reference ingest legitimately
-  calls the embeddings endpoint; a blanket panic passes the assertion for the
-  wrong reason and would also pass if ingest did nothing at all.
-- Rebuilding into a fresh database rather than dropping the live one. A rebuild
-  that never exercises deletion has not proved the projections are droppable.
-
-## Traps
-
-- Comparing M1.8 summaries by eye. The numbers move in the third decimal when the
-  gateway is under load; the committed `expected/` file plus an explicit
-  tolerance is the only version of this that stays honest over months.
-- Treating a changed baseline as a corpus problem. If update-rate shifts, first
-  confirm the gateway model has not changed underneath — `reasoning` and the 3B
-  controller are both moving targets, and misattributing that to this phase burns
-  a day.
-- Skipping assertion 11 because M5 is not built. The export *shape* is checkable
-  now, and discovering R in the training corpus during M5.3 means re-running an
-  expensive labelling pass.
-
----
-
-Background: [DESIGN.md](../DESIGN.md) — reference corpora, the tier model · [M1.8](M1.8-m1-gate.md) · [M4.2](M4.2-derived-filter.md)
diff --git a/tasks/M3.6.7-contextual-enrichment.md b/tasks/M3.6.7-contextual-enrichment.md
deleted file mode 100644
index 12c70a1..0000000
--- a/tasks/M3.6.7-contextual-enrichment.md
+++ /dev/null
@@ -1,42 +0,0 @@
-# M3.6.7 — Contextual Enrichment at Ingest
-
-| Field | Value |
-|---|---|
-| Phase | M3.6 — Reference corpora |
-| Size | M — 1–2 days |
-| Status | ⬜ Not started |
-| Depends | M3.6.1 (DocCorpusSource) |
-| Blocks | — |
-
-## Goal
-
-At ingest time, prepend each chunk with its context in the document hierarchy.
-This improves semantic search because queries using different terminology can
-still find relevant chunks.
-
-Inspired by Anthropic's Contextual Retrieval paper.
-
-## Example
-
-```
-BEFORE (raw chunk from heading "npm install"):
-  "Use 'npm ci' instead of 'npm install' for reproducible builds"
-
-AFTER (contextualized):
-  "From the Node.js Dependency Management guide, section npm install:
-   Use 'npm ci' instead of 'npm install' for reproducible builds"
-```
-
-The context gets embedded alongside the chunk's text, improving vector search.
-
-## Deliverables
-
-- `DocCorpusSource` enhanced to include breadcrumb path + section summary
-- Chunk rendering includes context header (auto-generated or manual)
-- Embedding happens on (context + chunk), not just chunk
-- Rebuild idempotence preserved
-
-## Tests
-
-- 5 unit tests (context generation, formatting, idempotence)
-- 3 integration tests (rebuild with enrichment, search improvement)
diff --git a/tasks/M3.6.8-chunk-deduplication.md b/tasks/M3.6.8-chunk-deduplication.md
deleted file mode 100644
index e76195b..0000000
--- a/tasks/M3.6.8-chunk-deduplication.md
+++ /dev/null
@@ -1,52 +0,0 @@
-# M3.6.8 — Chunk Deduplication at Ingest
-
-| Field | Value |
-|---|---|
-| Phase | M3.6 — Reference corpora |
-| Size | M — 1–2 days |
-| Status | ⬜ Not started |
-| Depends | M3.6.1 (DocCorpusSource), M3.7.7 (normalisation patterns) |
-| Blocks | — |
-
-## Goal
-
-Detect and deduplicate near-identical chunks at ingest time. Prevents the same
-error message, config snippet, or code sample from being stored 47 times from
-different runs/sources.
-
-## Approach
-
-**Probabilistic: MinHash-based duplicate detection**
-
-1. On each incoming chunk, compute MinHash signature (fast, space-efficient)
-2. Check against seen signatures with 95% accuracy threshold
-3. If match found: increment count on existing chunk, skip storage
-4. If new: store chunk + signature
-
-**Reuse from M3.7.7:** Normalisation patterns (strip_ansi, lowercase, remove
-extra whitespace) ensure similar content hashes identically.
-
-## Example
-
-```
-Run 1: npm ERR! 404 Not Found - react-dom@18.2.5
-  → stored as chunk #42
-  
-Run 2: npm ERR! 404 Not Found - react-dom@18.2.5
-  → same normalised hash → increment count on #42, don't store
-
-Run 3: npm ERR! 404 Not Found - react-dom@18.2.4
-  → different package version → new chunk #43
-```
-
-## Deliverables
-
-- `DeduplicationStore` with MinHash signatures
-- Integration with rebuild pipeline
-- Chunk count metadata tracking
-- Database schema extension (chunk.dedup_count)
-
-## Tests
-
-- 4 unit tests (MinHash collision testing, normalization)
-- 3 integration tests (rebuild deduplication, count tracking)