Context Compressor Skill Step 1: Identify Compressible Content Content types that can be compressed: Type Compression Strategy Code Keep signatures, summarize implementations Conversations Extract decisions, drop small talk Documentation Keep headings and key points Errors Keep message and location, drop stack frames Logs Keep patterns, drop repetitions Step 2: Apply Compression Techniques Technique 1: Decision Extraction Before: User: Should we use Redis or Memcached? Assistant: Let me analyze both options... [500 words of analysis] Recommendation: Redis for pub/sub support. User: Ok let's use Redis. After: Decision: Use Redis (chosen for pub/sub support) Technique 2: Code Summarization Before: // 100 lines of UserService implementation After: UserService: CRUD operations for users - Methods: create, read, update, delete, findByEmail - Dependencies: db, validator, logger - Location: src/services/user.js Technique 3: Error Compression Before: Error: Cannot read property 'id' of undefined at UserController.getUser (src/controllers/user.js:45:23) at Layer.handle [as handle_request] (node_modules/express/lib/router/layer.js:95:5) ... 20 more stack frames After: Error: Cannot read 'id' of undefined @ src/controllers/user.js:45 Cause: User object is null when accessing .id Step 3: Structure Compressed Output Use consistent formats:
Session Summary
Decisions Made
[D1] Use Redis for caching
[D2] JWT for authentication
Files Modified
src/auth/jwt.js (new)
src/config/redis.js (updated)
Open Items
[ ] Add rate limiting
- [ ] Write tests for JWT
- Step 4: Validate Compression
- Ensure critical info preserved:
- All decisions captured
- Key file locations retained
- Error causes documented
- Next steps clear
- Preserve Decisions
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- Never lose decision rationale
- Keep Locations
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- File paths and line numbers are critical
- Summarize, Don't Delete
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- Transform verbose content
- Use References
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- Point to files instead of including content
- Test Recovery
- Can you continue work from compressed context? Compress the last 10 messages for context handoff Example Response :
Context Summary (compressed from 10 messages)
Task Implementing user authentication with JWT
Progress 1. Created JWT utility (src/auth/jwt.js) 2. Added login endpoint (src/routes/auth.js) 3. Tests failing - mock issue
Key Decisions
Using RS256 for JWT signing (security over performance)
1-hour token expiry with refresh tokens
Current Issue Jest mock for jwt.sign not working Location: src/auth/ ** tests ** /jwt.test.js:23
Next Steps 1. Fix JWT mock 2. Add refresh token endpoint Rules Never lose decision rationale Always include file locations Test that work can continue from compressed context Workflow Integration This skill supports multi-agent orchestration by enabling efficient context management: Router Decision: .claude/workflows/core/router-decision.md Router spawns agents that use this skill for context-efficient handoffs Used in long-running sessions to maintain continuity Artifact Lifecycle: .claude/workflows/core/skill-lifecycle.md Compression patterns evolve with framework changes Session summaries feed into memory protocol Related Workflows: session-handoff skill for complete handoff protocol swarm-coordination skill for multi-agent context sharing Memory Protocol (MANDATORY) Before starting: cat .claude/context/memory/learnings.md After completing: New pattern -> .claude/context/memory/learnings.md Issue found -> .claude/context/memory/issues.md Decision made -> .claude/context/memory/decisions.md ASSUME INTERRUPTION: Your context may reset. If it's not in memory, it didn't happen.