| name | rn-harness-retro |
| description | Pipeline retrospective — evaluate the completed pipeline against Anthropic's 9 harness principles. |
rn-harness-retro — Harness Retrospective
Retrospective analysis of a project built with the RN Launch Harness pipeline. Evaluates the app against Anthropic's harness design principles and optionally verifies the app runs correctly.
"Every component in a harness encodes an assumption about what the model can't do on its own, and those assumptions are worth stress testing." — Anthropic
Trigger
- User invokes
/rn-harness-retro
- Called after the full pipeline completes (post Phase 10: Submit)
Arguments
Parse $ARGUMENTS for:
[project-dir] — Target project path (default: current directory)
--run-app — Attempt to build and run the app, verify it works on simulator
--deep — Deep analysis including source code review
Phase 1: Collect Harness Outputs
1.1 Read All Harness Artifacts
Read every file in docs/harness/ and docs/specs/:
docs/harness/state.md → Pipeline state
docs/harness/config.md → Configuration
docs/harness/contract.md → Contract (Generator-Evaluator agreement)
docs/harness/build-log.md → Build log (rounds, scores)
docs/harness/pipeline-log.md → Pipeline event log
docs/harness/plans/ → PRD and planning documents
docs/harness/feedback/ → QA feedback (all rounds)
docs/harness/handoff/ → Handoff documents (all rounds)
docs/harness/screenshots/ → Screenshots taken during evaluation
docs/specs/ → Spec files and progress dashboard
Read all files and reconstruct the full pipeline history.
1.2 Git History Analysis
git log --oneline --all
git log --format="%h %s" --since="$(cat docs/harness/state.md | grep created_at | cut -d' ' -f2)"
Trace the build/QA cycle from commit messages. Identify:
- Number of build rounds
- Generator vs Evaluator commits
- Phase transition points
1.3 App Run Verification (--run-app flag)
If --run-app is specified:
- Install dependencies:
npm install
- TypeScript check:
npx tsc --noEmit — must pass with 0 errors
- Lint check:
npm run lint — must pass with 0 errors
- Start Metro bundler:
npx expo start
- iOS Simulator:
npx expo run:ios — verify app launches without crash
- Android Emulator:
npx expo run:android — verify app launches without crash (if available)
- Spot-check contract criteria: Pick 3-5 key criteria from contract.md and manually verify
- Console errors: Check Metro output for red/yellow box errors
Record all results for the retro report.
Phase 2: Evaluate Against Anthropic's Harness Principles
Reference: Harness design for long-running application development
Evaluate the pipeline's adherence to each of the following 9 principles. For each principle, check the evidence, apply the checklist, and assign a star rating.
P1. Generator-Evaluator Separation
"Separating the agent doing the work from the agent judging it proves to be a strong lever."
Checklist:
Evidence sources: pipeline-log.md for generator/evaluator alternation, feedback/ files for FAIL verdicts
P2. Evaluator Skepticism
"Out of the box, Claude is a poor QA agent... would identify legitimate issues, then talk itself into deciding they weren't a big deal."
Checklist:
Evidence sources: feedback/ files score trends, specificity of FAIL reasons
P3. Contract Negotiation Quality
"The generator proposed what it would build and how success would be verified, and the evaluator reviewed that proposal."
Checklist:
Evidence sources: contract.md criteria count and coverage mapping
P4. File-Based Handoff
"Communication was handled via files: one agent would write a file, another agent would read it."
Checklist:
Evidence sources: handoff/ file existence, state.md change history
P5. No Sprints (V2 Architecture)
"I started by removing the sprint construct entirely."
"The model handled 2+ hours of coherent building without sprint decomposition."
Checklist:
Evidence sources: build-log.md round structure
P6. Screenshot-and-Study
"The evaluator would navigate the page on its own, screenshotting and carefully studying the implementation."
Checklist:
Evidence sources: screenshot files, feedback references to visual verification
P7. Simplicity
"Find the simplest solution possible, and only increase complexity when needed."
Checklist:
Evidence sources: pipeline-log.md phase durations, each phase's actual contribution
P8. Cost-Quality Tradeoff
20x cost increase justified by 20x output quality improvement.
Checklist:
Evidence sources: build-log.md score trends, total duration
P9. Test Deduplication
Comprehensive testing should avoid redundant test cases across evaluation passes.
Checklist:
Evidence sources: feedback/ files test case comparison across rounds
Phase 3: App Verification (--run-app)
If --run-app was specified, compile the results from Phase 1.3:
| Item | Result | Notes |
|---|
| npm install | PASS/FAIL | [error details] |
| TypeScript check | PASS/FAIL | [error count] |
| Lint check | PASS/FAIL | [error count] |
| iOS Simulator launch | PASS/FAIL | [crash details] |
| Android Emulator launch | PASS/FAIL | [crash details] |
| Contract spot-check | N/M PASS | [failed items] |
| Console errors | N found | [severity] |
Phase 4: Write Retro Report
Generate docs/harness/retro.md:
# Harness Retrospective — [Project Name]
> Generated: [date]
> Pipeline duration: [start ~ end]
> Total rounds: [N]
> Final QA score: [score]
## App Verification Results
| Item | Result | Notes |
|------|--------|-------|
| Build | PASS/FAIL | [error details] |
| TypeScript | PASS/FAIL | [error count] |
| Lint | PASS/FAIL | [error count] |
| iOS Launch | PASS/FAIL | [details] |
| Android Launch | PASS/FAIL | [details] |
| Contract Spot-check | N/M PASS | [failed items] |
| Console Errors | N found | [severity] |
## Anthropic Principle Adherence
| Principle | Rating | Summary |
|-----------|--------|---------|
| P1. Generator-Evaluator Separation | ★★★☆☆ | [one-line assessment] |
| P2. Evaluator Skepticism | ★★★☆☆ | [one-line assessment] |
| P3. Contract Negotiation | ★★★☆☆ | [one-line assessment] |
| P4. File-Based Handoff | ★★★☆☆ | [one-line assessment] |
| P5. No Sprints (V2) | ★★★☆☆ | [one-line assessment] |
| P6. Screenshot-and-Study | ★★★☆☆ | [one-line assessment] |
| P7. Simplicity | ★★★☆☆ | [one-line assessment] |
| P8. Cost-Quality Tradeoff | ★★★☆☆ | [one-line assessment] |
| P9. Test Deduplication | ★★★☆☆ | [one-line assessment] |
### Detailed Analysis per Principle
#### P1. Generator-Evaluator Separation
**Rating: ★★★☆☆**
[Evidence-based detailed analysis. Include checklist results.]
... (repeat for P2 through P9)
## Keep (What Went Well)
1. [Specific example with evidence]
2. ...
## Improve (What Needs Improvement)
1. [Specific example with improvement direction]
2. ...
## Try (Experiments for Next Project)
1. [Ideas to experiment with in the next pipeline run]
2. ...
## Harness Improvement Suggestions
[Based on this project's experience, improvement points for rn-launch-harness itself]
Rating Scale
| Rating | Meaning |
|---|
| ★★★★★ | Principle perfectly implemented. On par with Anthropic's reference examples. |
| ★★★★☆ | Principle well followed. Minor room for improvement. |
| ★★★☆☆ | Basics followed but some gaps or superficial adherence. |
| ★★☆☆☆ | Principle only partially followed. Substantive improvement needed. |
| ★☆☆☆☆ | Principle barely implemented. |
Completion
After writing the retro report:
- Git commit:
docs: harness retrospective report
- Present the top 3 key findings to the user as a summary
- If
--deep was used, include specific code-level observations in the report