/compound

name: compound
description: |
  This skill should be used when the user says "/compound", "compound this",
  "document learnings", "save what we learned", or after completing a PR.
  Extracts knowledge from PR context and saves to docs/learnings/.
allowed-tools:
  - Read
  - Grep
  - Glob
  - Bash
  - Write
  - Edit
  - AskUserQuestion

Compound Skill

Extracts knowledge from PR context and saves structured documentation to `docs/learnings/`.

Workflow

Phase 1: Context Collection

1. **Identify PR number/branch**

• Use PR number if provided as argument
• Otherwise, find PR from current branch: `gh pr view --json number,body,title`
• **If no PR exists**: Prompt user to enter PR number directly or confirm proceeding without PR

2. **Extract Plan path**

• Find Plan path pattern in PR body: `.hoyeon/specs/{name}/PLAN.md`
• Regex: `\.hoyeon/specs/[^/]+/PLAN\.md`
• **If no Plan path found**: Prompt user to enter spec name directly or select from `.hoyeon/specs/` directory listing

3. **Derive Context path**

• Extract spec name from Plan path
• Context directory: `.hoyeon/specs/{name}/context/`

4. **Parallel collection** (run following commands simultaneously, skip if files don't exist)

   # Context files (treat as empty if not found)
   cat .hoyeon/specs/{name}/context/learnings.json 2>/dev/null || echo ""
   cat .hoyeon/specs/{name}/context/decisions.md 2>/dev/null || echo ""
   cat .hoyeon/specs/{name}/context/issues.json 2>/dev/null || echo ""

   # PR comments and reviews (collect as JSON for stability)
   gh pr view {pr_number} --json comments,reviews

**Error Handling:**

• If no context files exist AND no PR comments → Notify user and request manual input
• At least 1 source required to proceed with document generation

Phase 2: Knowledge Extraction & Classification

2.1 Extract Valuable Feedback from PR Comments

**Criteria for valuable feedback:**

• Code improvement suggestions
• Bug/issue identification
• Pattern/best practice mentions
• "This would be better" type advice
• Comments left with approval

**Filter out:**

• Simple questions ("What is this?")
• Confirmation requests ("Is this correct?")
• Approval-only comments ("LGTM", "Approved")
• Bot comments

**Extraction keywords:**

• "suggest", "recommend", "better", "instead"
• "pattern", "practice", "convention"
• "issue", "bug", "fix"
• "learned", "TIL", "note"

**Extracted information:**

• author
• body
• file_path (if inline comment)
• created_at

2.2 Analyze Context Files

| File | Purpose | |------|---------| | learnings.json | Structured learnings | | decisions.md | Decision rationale | | issues.json | Structured issues |

2.3 Synthesize

1. Assess documentation value from collected sources 2. Check for duplicates: Search `docs/learnings/` 3. Classify problem type - Refer to `references/problem-types.md` (relative to this skill directory) 4. Generate tags

Phase 3: Document Generation

1. **Generate YAML frontmatter**

   pr_number: {PR_NUMBER}
   date: {YYYY-MM-DD}
   problem_type: {TYPE}
   tags: [{TAGS}]
   plan_path: {PLAN_PATH}

2. **Write document using template**

• Template location: `templates/LEARNING_TEMPLATE.md` (relative to this skill directory)
• Read template and substitute placeholders

3. **Determine filename**

• Format: `{YYYY-MM-DD}-{short-title}.md`
• Example: `2024-01-15-api-error-handling.md`

4. **Save**

• Path: `docs/learnings/{filename}.md`

5. **Add cross-references** (if related documents exist)

• Add new document link to Related section of existing documents

Usage Examples

# Specify PR number
/compound 123

# Use PR from current branch
/compound

Output

Outputs the created document path and summary:

Created: docs/learnings/2024-01-15-api-error-handling.md

Summary:
- Problem Type: error-handling
- Tags: api, typescript, validation
- Sources: learnings.json, 2 PR comments

---

<!-- TODO: Future extensions --> <!-- - [ ] Session ID based user feedback collection --> <!-- - [ ] CLAUDE.md auto-update suggestions --> <!-- - [ ] Detect existing document UPDATEs --> <!-- - [ ] Auto-categorization by problem_type (docs/solutions/{type}/) -->