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Get Started Free →Use this skill when extracting session patterns into reusable learnings. Three modes: analyze (extract from session history), review (edit/manage existing learnings), list (display active learnings). Manages .orchestrator/metrics/learnings.jsonl.
| Test case | Without → With | Effect | Δ tokens | Δ turns |
|---|---|---|---|---|
| case-04 | ✗→✓ | ▲ Improved | -9% | 0% |
| case-08 | ✗→✓ | ▲ Improved | 45% | 0% |
| case-09 | ✗→✓ | ▲ Improved | 27% | 0% |
| case-10 | ✗→✓ | ▲ Improved | -29% | 0% |
| case-11 | ✗→✓ | ▲ Improved | -15% | 0% |
CRITICAL: Run HARNESS_DIR=$(epic path) first. NEVER use .harness/ in the project directory.
You are the Evolution Engine — analyze past sessions to improve skills.
/evolve (default) — Run evolution now$HARNESS_DIR/obs/$HARNESS_DIR/evolved//evolve status — Show evolution dashboardRead $HARNESS_DIR/metrics.json and $HARNESS_DIR/evolution.jsonl, then display:
## Evolution Dashboard
### Overview
- Sessions analyzed: {total_sessions}
- Average success rate: {avg_success_rate}%
- Best score: {best_score} (session: {best_session})
- Trend: {trend} ({score_history.length} data points)
- Stagnation count: {stagnation_count} / 3 (rollback at 3)
### Score History (last 5 sessions)
| Session | Success Rate | Avg Score | Observations | Tool Success | Output Quality |
|---------|-------------|-----------|--------------|-------------|---------------|
### Evolved Skills
(list $HARNESS_DIR/evolved/*/SKILL.md with name and description from frontmatter)
### Last Session Analysis
(read last entry from evolution.jsonl)
- Error patterns: {error_patterns}
- Failure patterns: {failure_patterns[].pattern_type}
- Skills seeded: {skills_seeded}
- Skills rolled back: {skills_rolled_back}
- Analysis: {analysis_summary}/evolve history — Long-term analysisRead $HARNESS_DIR/evolution.jsonl (full history), then display:
## Evolution History
### Trend Over Time
| Session # | Date | Success Rate | Avg Score | Skills | Patterns |
|-----------|------|-------------|-----------|--------|----------|
### Cumulative Pattern Frequency
| Pattern | Total Count | First Seen | Last Seen |
|---------|-------------|------------|-----------|
### Skill Effectiveness
| Skill | Sessions Active | Avg Score With | Avg Score Without | Delta |
|-------|----------------|----------------|-------------------|-------|
### Dispatch Analysis
| Skill | Times Invoked | Top Trigger Signals |
|-------|--------------|---------------------|/evolve rollback — Undo last evolution$HARNESS_DIR/evolved_backup/ exists, restore it to $HARNESS_DIR/evolved/$HARNESS_DIR/evolution.jsonl for last entry, remove skills seeded in that entry/evolve reset — Clear all evolution data$HARNESS_DIR/evolved/, $HARNESS_DIR/evolved_backup/metrics.json and evolution.jsonlObserve (PostToolUse — multi-dimensional scoring)
↓ $HARNESS_DIR/obs/session_YYYYMMDD.jsonl
Analyze (Stop or /evolve)
↓ SessionAnalysis: per-tool, per-ext, score distribution
↓ Pattern detection: repeated_same_error, fix_then_break, long_debug_loop, thrashing
Seed (auto-generate targeted skills)
↓ 4 seeding paths: pattern / weak tool / weak file type / high-freq error
Gate (validate: format, dedup, cap of 10)
↓ Stagnation check: 3 sessions no improvement → rollback to best checkpoint
Reload (next session resume reports metrics + loads evolved skills)When epic-harness reflect seeds a skill, it emits a pending-synthesis manifest to $HARNESS_DIR/pending_synth.jsonl (failure evidence + template body). To synthesize a better body:
$HARNESS_DIR/pending_synth.jsonl; for each record with status: "pending":tool or model) with the manifest's prompt_guidance + evidence, instructing it to write a markdown skill body with the required sections (## Process, ## Anti-Rationalization, ## Evidence Required, ## Red Flags).
bash epic-harness evolve accept-synth --skill <name> --file <body.md>
skill, and marks the manifest consumed.
If no host runs accept-synth, the template body persists — synthesis can only improve a skill, never block it.
0.5 × tool_success + 0.3 × output_quality + 0.2 × execution_costOther measured skills in the registry, with their headline benchmark lift.