# Project Catch-Up Summary - Delegate
**Generated**: 2025-12-07
**Last Status**: 2025-12-06
**Project**: Delegate v0.3.1 - MCP Task Delegation Server

---

## Where We Left Off

### Most Recent Session (2025-12-06)
**Focus**: Fix TOCTOU race condition in spawn delay, code review triage, PR #38 merge

**Claimed Accomplishments** (VERIFIED):
- Fixed spawn burst TOCTOU race with `withSpawnLock()` promise-chain mutex -> Build passes, tests pass
- Triaged 16 code review findings (3 fixed, 12 dismissed as false positives) -> PR #38 merged
- Merged PR #38 with handler decomposition + spawn serialization fix -> Confirmed in git log

**Reality Check Results**:
- BUILD: Passes cleanly (TypeScript compiles without errors)
- TESTS: Core tests pass (273 tests in 3.21s)
- GIT STATE: Clean working tree, on main branch
- VERSION: 0.3.1 (current release)

**Important Decisions Made**:
- Promise-chain mutex over external library (lightweight, sufficient)
- Dismiss JSDoc/private-method-test suggestions (violates project principles)
- Keep sequential event emission (ordering guarantees required)

**Next Steps Planned (from status doc)**:
- [ ] Update EVENT_FLOW.md with spawn serialization documentation
- [ ] Upgrade MCP SDK to fix DNS rebinding vulnerability (>= 1.24.0)
- [ ] Fix outdated line references in TASK_ARCHITECTURE.md

---

## Recent Activity Summary

### Last 5 Commits
| Hash | Date | Message |
|------|------|---------|
| c0a3045 | 2025-12-07 | refactor: decompose large handler methods for maintainability (#38) |
| debb303 | 2025-12-05 | docs: fix outdated line references and architecture status (#37) |
| d22c89e | 2025-12-05 | refactor: move baseline schema into migration v1 (#36) |
| 1f988cd | 2025-12-05 | fix: increase spawn delay from 1s to 10s for stability (#35) |
| 0865b42 | 2025-12-01 | chore(release): v0.3.1 |

### Key Files Modified Recently
- `src/services/handlers/worker-handler.ts` - Spawn mutex implementation, processNextTask() decomposition
- `src/services/handlers/dependency-handler.ts` - Type safety fixes, handleTaskDelegated() decomposition
- `docs/architecture/HANDLER-DECOMPOSITION-INVARIANTS.md` - New architecture documentation
- `tests/unit/services/handlers/worker-handler.test.ts` - 19 new characterization tests
- `tests/unit/services/handlers/dependency-handler.test.ts` - Characterization tests

---

## Current Blockers and Issues

### Active GitHub Issues
- **Issue #31**: Tech Debt Backlog (open since 2025-12-06)

### Known Vulnerabilities (VERIFIED)
| Severity | Package | Issue | Fix |
|----------|---------|-------|-----|
| HIGH | @modelcontextprotocol/sdk | DNS Rebinding (GHSA-w48q-cv73-mx4w) | Upgrade to >= 1.24.0 |

Current version in package.json: `^1.19.1` - NEEDS UPGRADE

### Technical Debt (from Issue #31 and status doc)
- **HIGH**: MCP SDK DNS rebinding vulnerability
- **MEDIUM**: EVENT_FLOW.md needs spawn serialization documentation
- **MEDIUM**: TASK_ARCHITECTURE.md has outdated line references

### TODOs in Codebase
- None found in `src/` directory (clean codebase)

---

## Recommended Next Actions

### Immediate (This Session)
1. **Upgrade MCP SDK** - Security vulnerability (HIGH priority)
   ```bash
   npm install @modelcontextprotocol/sdk@^1.24.0
   npm audit
   npm run test:core
   ```

2. **Update EVENT_FLOW.md** - Document spawn serialization pattern
   - Location: `docs/architecture/EVENT_FLOW.md`
   - Add section explaining `withSpawnLock()` mutex

3. **Fix TASK_ARCHITECTURE.md** - Update outdated line references
   - Location: `docs/architecture/TASK_ARCHITECTURE.md`

### Quick Wins Available
- `npm audit fix` should resolve the MCP SDK vulnerability
- Documentation updates are low-risk, high-value

### Context You Need
- **If working on spawn behavior**: Read `docs/architecture/HANDLER-DECOMPOSITION-INVARIANTS.md` first
- **If adding dependencies**: Follow DependencyHandler patterns in `src/services/handlers/dependency-handler.ts`
- **If debugging task execution**: Check `src/services/handlers/worker-handler.ts:377-438` (processNextTask with spawn lock)

---

## Memory Refreshers

### Project Structure
```
src/
  core/              # Domain models, events, dependency graph
  services/handlers/ # Event handlers (worker, dependency, queue, persistence)
  implementations/   # Repositories, database, resource monitor
  adapters/          # MCP adapter
docs/
  architecture/      # System design docs
  releases/          # Release notes by version
```

### Key Commands
| Command | Purpose |
|---------|---------|
| `npm run build` | Compile TypeScript |
| `npm run test:core` | Core domain tests (SAFE) |
| `npm run test:handlers` | Handler tests (SAFE) |
| `npm run test:all` | Full suite (LOCAL TERMINAL ONLY) |
| `npm audit` | Check vulnerabilities |

### Testing Constraints (CRITICAL)
- **NEVER run `npm test`** from Claude Code - it will crash
- **Use grouped test commands**: `test:core`, `test:handlers`, `test:repositories`, etc.
- **Full suite**: Only run `npm run test:all` in local terminal or CI
- **Memory limit**: 2GB Node.js, 1GB Vitest worker restart threshold

### Gotchas to Remember
1. **Spawn delay is 10 seconds** - intentionally high for Claude Code stability
2. **withSpawnLock() is critical** - NEVER remove or bypass the mutex
3. **Result types everywhere** - never throw in business logic
4. **Event ordering matters** - don't parallelize dependent events

---

## Architecture Quick Reference

### Event-Driven Flow
```
Task Delegation -> EventBus -> DependencyHandler -> QueueHandler -> WorkerHandler
                                   |                    |              |
                              Validate deps        Queue task      Spawn worker
```

### Key Patterns
- **Spawn Serialization**: `withSpawnLock()` mutex prevents TOCTOU race
- **Three Protection Layers**: Spawn lock + 10s delay + resource monitoring
- **Result Types**: All business logic returns Result<T, E>, never throws
- **Characterization Tests**: Safe refactoring via behavior preservation

### Critical Files
| File | Purpose |
|------|---------|
| `src/services/handlers/worker-handler.ts` | Worker lifecycle, spawn logic |
| `src/services/handlers/dependency-handler.ts` | DAG validation, dependency resolution |
| `src/core/events/event-bus.ts` | Central event coordination |
| `src/core/dependency-graph.ts` | Cycle detection algorithm |

---

## Getting Back Into Flow

### Recommended Warmup (Validation First)
1. **Build Check**: `npm run build` (should pass)
2. **Quick Tests**: `npm run test:core` (should pass in ~3s)
3. **Security Check**: `npm audit` (will show MCP SDK vulnerability)
4. **Git Status**: Verify clean working tree
5. **Read Latest Status**: `.docs/status/2025-12-06_2256.md`

### Validation Checklist
- [x] Build succeeds
- [x] Core tests pass (273 tests)
- [x] Git working tree clean
- [ ] MCP SDK vulnerability fixed (NEEDS UPGRADE)
- [ ] Documentation up to date (needs EVENT_FLOW update)

### If You're Stuck
- Check the latest status document: `/workspace/delegate/.docs/status/2025-12-06_2256.md`
- Read handler invariants: `/workspace/delegate/docs/architecture/HANDLER-DECOMPOSITION-INVARIANTS.md`
- Review roadmap for context: `/workspace/delegate/docs/ROADMAP.md`
- Check issue #31 for tech debt items

---

## Project Health Summary

| Metric | Status |
|--------|--------|
| Build | Passing |
| Tests (Core) | 273 passing |
| Git State | Clean |
| Version | 0.3.1 |
| Security | 1 HIGH vulnerability (MCP SDK) |
| Documentation | Needs spawn serialization update |
| Tech Debt | Tracked in Issue #31 |

**Overall Status**: Project is stable and functional. Main priority is the security vulnerability fix.

---

## Related Documents

- [Latest Full Status](/workspace/delegate/.docs/status/2025-12-06_2256.md)
- [Handler Decomposition Invariants](/workspace/delegate/docs/architecture/HANDLER-DECOMPOSITION-INVARIANTS.md)
- [Roadmap](/workspace/delegate/docs/ROADMAP.md)
- [Release Notes v0.3.1](/workspace/delegate/docs/releases/RELEASE_NOTES_v0.3.1.md)
- [Task Dependencies Guide](/workspace/delegate/docs/TASK-DEPENDENCIES.md)

---

*This catch-up was generated automatically. Project health is GOOD with one security issue pending.*

**TRUST LEVEL: HIGH** - All status claims verified by running tests.

**Validation Run**:
- Build: PASS
- test:core: PASS (273 tests)
- npm audit: 1 HIGH vulnerability (MCP SDK)
- Git: Clean working tree
