---
name: harvest-loop
description: A self-evolution pipeline that runs automatically after field sessions end. field-harvest (pattern extraction) → contention-layer (collision signals) → [Agent(subagent_type="challenger") + persona-innovator parallel] → synthesizer (challenger/innovator collision harvest) → Critic isolated Agent (SAGE automated critique) → harness-doctor (health check) → verify-bidirectional (consistency validation) → curator (skill lifecycle management) — 8 steps. Session learnings are automatically absorbed back into the FH ecosystem so the harness evolves on its own. In the main development environment, runs automatically at session end. For external FH users, proposes execution first. Triggered by "session harvest", "learning absorption", "fh evolution", or "harvest-loop". (The phrase "run the pipeline" is ceded to pipeline-conductor to avoid a trigger collision — for end-to-end verification sweeps use pipeline-conductor.)
user-invocable: true
allowed-tools: ["Read", "Write", "Bash", "Grep", "Glob", "Agent"]
model: opus
---

# harvest-loop — Field Session → FH Self-Evolution Pipeline

> Automatically absorbs patterns/conflicts/discoveries from field sessions back into the FH ecosystem.
> Internalizes as a pipeline the return loop from field projects to the harness that was previously done manually.
> One of the core functions is real-time detection and blocking of **Semantic Drift** — where agent terminology gradually diverges in meaning as sessions grow longer.

## Operation Modes

| Mode | Description | Trigger |
|---|---|---|
| **Forced mode** | Auto-runs at end of local development session. Executes without approval, only confirms final suggestions | Session wrap-up rules in hub CLAUDE.md |
| **Lightweight mode** | Immediate harvest after Wave completion. Skip Steps 3/3.5/4 — prioritize fast recording | agent-composer Step 4-c (2+ new files or 3+ existing files changed, **or M-tier resolved**) |
| **Proposal mode** | External FH users — confirms "run harvest-loop?" before executing | User utterance or `/harvest-loop` |

**Simplification guard**: Sessions that only browsed/explored (no code changes or outputs) auto-skip even in forced mode.

**Lightweight mode Done When**:
```
Step 0 (Regression Guard) + Step 1 (field-harvest) + Step 2 (contention-layer) + Step 5 (verify-bidirectional) complete
+ harvested pattern summary 1~3 lines output
+ "run full harvest-loop?" proposed (if patterns found)
+ [Card update prohibited] Do NOT update reference_next_session_starter.md in lightweight mode alone
```

**Early Trigger** (mid-session): Same pattern 3+ times · same skill fails 2+ consecutive times · session 2+ hours elapsed → "Early harvest condition detected. Run mid-session harvest?" If Y → field-harvest → contention-layer → verify-bidirectional only.

---

## Pipeline Structure

```
Session end
    │
[Step 0-a] FH asset change detection → auto-quench
    │  git diff --name-only HEAD | grep -E "SKILL\.md|\.claude/rules/|templates/|CLAUDE\.md"
    │  → 1+ FH assets changed: run full 3-axis gate
    │  → No changes: proceed to Step 0-b immediately
    │
[Step 0-b] Card cross-check — reconstruct completed items (no memory dependency)
    │  Read reference_next_session_starter.md + fh_completed_{today}.md + git log
    │  → Generate removal candidate list from 3-source cross-check
    │
[Step 0-c] Edit Manifest Verification + Memory Hygiene
    │  edit-manifest VERIFY: check pending predictions in edit_manifest.yaml
    │  memory-hygiene scan: staleness check on memory/*.md entries (skip if < 7 days)
    │
[Step 0] Regression Guard
    │  Check: does anything from this session conflict with or regress a validated skill?
    │  → Regression detected: flag, route to contention-layer
    │  → No regression: proceed
    │
[Step 1] field-harvest
    │  Scan field git diff / outputs → extract patterns (proceed if 3+, skip if fewer)
    │
[Step 2] contention-layer
    │  Compare patterns ↔ existing FH skills → collision = new skill candidate signal
    │
[Step 3a] challenger (Agent)     [Step 3b] persona-innovator  ← parallel
    │  Attack existing skills         Propose new skill candidates
    │
[Step 3.5] synthesizer
    │  Cross-synthesize attack ↔ proposal → readjust grades (HIGH/MED/LOW)
    │
[Step 3.75] Critic (isolated Agent — SAGE pattern)
    │  Independent critique of synthesizer proposals → PASS / CONDITIONAL PASS / FAIL
    │
[Step 4] harness-doctor
    │  Health check when adding candidates (Done When exists? ≥70% overlap?)
    │
[Step 5] verify-bidirectional
    │  Bidirectional consistency check on candidate skill
    │
Output final proposal list → Y: PR creation / N: persist to tracks/_meta/fh_signal
    │
[Step 6] Curator lifecycle review (auto-run after Y)
    │  SKILL.md STALE/merge candidates + Memory self-correction
```

---

## Execution Instructions

### Step 1 — field-harvest
`/field-harvest --since 1d` — Fewer than 3 patterns → auto-skip + output "no session harvest targets".

### Step 2 — contention-layer
`/contention-layer [field-harvest output patterns]`

| Collision type | Routing |
|---|---|
| Overlaps with existing skill | Existing skill enhancement candidate |
| New area not covered | New skill candidate |
| Two skills conflict | Mediation skill candidate |

### Step 3 — Parallel challenger + innovator
**3a challenger**: "Does this discovery overturn existing skill X?" / "Doesn't existing skill already handle this?" / "Does adding this simplify or complicate FH?"
**3b innovator**: Field pattern → abstraction → naming candidates + Done When draft required.

### Step 3.5 — synthesizer

| devil attack | innovator proposal | synthesizer verdict |
|:---:|:---:|---|
| S-tier attack | Proposal for that area | **HIGH** — immediate reflection candidate |
| S-tier attack | No proposal | **HIGH** — fix existing skill weakness immediately |
| No attack | Proposal exists | **MED** — re-review in next wave |
| Attack overturns proposal | — | Proposal **rejected** — persist as fh_signal on hold |

**Fallback** (deep-insight not installed): Inline synthesis. Apply same judgment matrix. If quality low → Step 3.75 Critic processes as CONDITIONAL PASS.

**Step 3.5-X** (optional): Cross-session 2nd validation when 2+ HIGH-grade items exist. External CLI (gemini/codex) or cross-session Claude. Items flagged as over-promoted → downgrade HIGH → MED. External CLI availability is resolved via `knowledge/shared/harness-core/multi_model_sidecar_strategy.md §Sidecar Engine Resolution Protocol` (Tier 1→2→3; Tier 3 = cross-session Claude — no hard-fail when no external CLI exists).

> **Detail**: See `SKILL_detail.md §Step3-5X` — bash execution scripts for external CLI and cross-session Claude fallback — read when running Step 3.5-X validation.

### Step 3.75 — Critic (Isolated Agent)

> Source: SAGE (arXiv 2603.15255). Isolation = Critic does not inherit synthesizer reasoning chain → resolves Cost of Consensus.

Critic evaluation: Done When logic validation · failure mode exploration (2+ edge cases) · claim vs. implementation alignment · scope appropriateness (Too Narrow / Too Broad).

FAIL routing: First FAIL → 1 re-synthesis allowed. FAIL after re-synthesis → auto-persist as `fh_signal` on hold. Maximum retries: **1**.

> **Detail**: See `SKILL_detail.md §Step3-75` — Critic isolated Agent() call format, evaluation items table, FAIL routing, Post-Core-Skill Critic connection — read when executing Step 3.75.

### Step 4 — harness-doctor
`/harness-doctor --scope new-candidates` — Check: Done When exists · ≥70% overlap with existing skills · self-reference structure.

### Step 5 — verify-bidirectional
`/verify-bidirectional [new skill draft]` — If A references B, does B back-reference A?

### Step 6 — Curator Lifecycle Review

**6-1 SKILL.md Lifecycle**: 30+ day unused → [STALE] candidate. `pinned: true` → never touch. ≥70% overlap → merge candidate suggestion. **> 300 lines AND no `SKILL_detail.md`** → propose `/skill-splitter` (governance-semantic split — not compression; the grew-through-harvest pattern is a natural split trigger).

**6-1-a Archive-candidate auto-tag**: When 0 invocations in 30 days detected (cross-check `tracks/_meta/skill_usage.md`), auto-append `#archive-candidate` tag to that skill's CATALOG.md entry. No file deletion — tag only. User reviews tagged entries at next session start.

**6-2 Memory Self-Correction**: INDEX-ORPHAN (in MEMORY.md but file missing → auto-remove) · FILE-ORPHAN (file exists, not indexed → confirm with user) · MEM-STALE (30+ day unmodified → confirm with user).

**Memory curator safety**: Only INDEX-ORPHAN removal is auto-allowed. Actual file deletion absolutely prohibited without explicit approval. `type: reference` items with 🔑 keywords excluded from STALE detection.

**6-a Skill Usage Leaderboard**: Record skills called this session in `tracks/_meta/skill_usage.md`. Flag 4+ weeks no-call → deprecation candidate.

**6-b Harness Evolution Cadence** (4-week cycle): Scan skills with `complexity_routing`. Aggregate escalation records from `fh_signal_*.md`. Valid conditions = keep; never activated in 4 weeks = removal candidate; pattern in fh_signal = addition candidate. No auto-modification — output candidates then require user approval.

> **Detail**: See `SKILL_detail.md §Step6-Detail` — bash scripts for STALE detection, memory scan, skill usage leaderboard, evolution cadence aggregation — read when executing Step 6.

---

## Observability Hook (glass-box self-improvement)

Every evolution decision must leave a 3-part trace in `tracks/_meta/edit_manifest.yaml`:
- **(a) what changed** — file + diff summary
- **(b) predicted effect** — `predicted_impact` + `predicted_measurable_by`
- **(c) verify checkpoint** — `validation_status` flipped at next Step 0-c VERIFY

A proposal accepted without a recorded prediction is a black-box edit — flag, do not silently apply.

> **Detail**: See `SKILL_detail.md §Observability` — full observability hook spec and trace format.

---

## Output Format

```
## harvest-loop Execution Results

Session: [date] [project name]
field-harvest: [N patterns extracted]
contention-layer: [N collision signals]
synthesizer: [HIGH N / MED N / rejected N]

### Final Proposals (sorted by synthesizer grade)
| # | Type | Target | Grade | devil | innovator | synthesizer verdict |
|:---:|---|---|:---:|---|---|---|

→ Y: Create PR / draft skill file
→ N: Persist to tracks/_meta/fh_signal_YYYY_MM_DD_{slug}.md

### [Required final step] Session card update (proof gate)
Read reference_next_session_starter.md → apply Step 0-b removal list → add new priorities
→ output "BEFORE N items → AFTER M items (removed: [list])" — required
→ No diff (N=M) = warning + Step 0-b re-check obligation

**Natural-language close (4th source)**: Even without git log match, items with these patterns stated in session → treated as closed, remove immediately:
- "not possible / confirmed impossible" · "no response + N weeks elapsed" → abandoned
- "mutual citation confirmed" · "merged" · "cancelled" · "no longer needed"
- User says "stop monitoring" · "close this" · "remove it"
```

> **Detail**: See `SKILL_detail.md §Output-Detail` — 2-source mode (when fh_completed absent), exact match criteria, natural-language close edge cases — read when reconstructing session card without fh_completed file.

---

## Linked Skills

| Situation | Linked skill |
|---|---|
| 3+ new skill candidates | `/agent-composer` for dispatch plan |
| Design existing skill enhancement direction | `/meta-prompt-builder` |
| Validate candidates from external user perspective | `fh-meta:hub-persona-auditor` |
| Review before sharing with team | `/apex-review` |
| Self-marketing pattern discovered as HIGH P10 | `/harness-doctor --lint` auto-propose |
| Edit predictions to verify / rejected buffer | `fh-meta:edit-manifest` (Step 0-c) |
| Stale memory entries to re-verify | `fh-meta:memory-hygiene` (Step 0-c) |

---

## Done When

```
All stages Step 0-c → 0 → 1 → 2 → 3 (parallel) → 3.5 → 3.75 → 4 → 5 complete
+ Step 0-c: edit-manifest pending entries verified + memory-hygiene scan run
+ Step 3.75 Critic verdict received (PASS/CONDITIONAL PASS/FAIL stated) before Step 4
+ synthesizer grade readjustment complete (rejected candidates separated)
+ Final proposal list output (sorted by HIGH/MED)
+ User Y/N approval gate complete
+ (If Y) Step 6 Curator complete
  → 6-1: STALE candidate list + merge candidates
  → 6-2: INDEX-ORPHAN/FILE-ORPHAN/MEM-STALE detection results
+ [Required] reference_next_session_starter.md delta update complete
  → BEFORE N items → AFTER M items diff output required (proof gate)
  → No diff (N=M) = warning + Step 0-b re-check
  → Completed items remaining = bug (Done When not met)
```