# Episode Relationships Feature - Roadmap

**Last Updated**: 2026-01-31  
**Feature Version**: v0.1.14  
**Overall Progress**: 20% Complete (Phase 1 ✅)

---

## Executive Summary

The Episode Relationships & Dependencies feature enables powerful workflow modeling, dependency tracking, and hierarchical organization of episodes. This roadmap outlines the 6-phase implementation plan spanning **9-15 days** of development effort.

**Key Milestones**:
- ✅ **Phase 1 Complete**: Storage foundation (1,169 LOC, 11 tests, 100% coverage)
- ⏳ **Phases 2-6**: Business logic, integration, tools, CLI, testing (2,600+ LOC, 105+ tests)

---

## Vision & Goals

### Problem Statement

Currently, episodes are independent entities with no way to model:
- **Dependencies**: "Episode B requires Episode A to be completed first"
- **Hierarchies**: "Epic → Stories → Subtasks"
- **Workflows**: "Episode C follows Episode B"
- **Relationships**: "Episode X is related to/duplicates/blocks Episode Y"

### Solution

Implement a comprehensive relationship system with:
1. ✅ Flexible relationship types (7 types)
2. ✅ Robust storage layer with indexes
3. ⏳ Cycle detection and validation
4. ⏳ Graph algorithms for traversal
5. ⏳ User-facing tools (MCP + CLI)

### Success Metrics

| Metric | Target | Current |
|--------|--------|---------|
| Feature Completeness | 100% | 20% |
| Test Coverage | >92% | 100% (Phase 1) |
| Performance (P95) | <100ms | TBD |
| User Adoption | >50% of workflows | 0% (not released) |
| Bug Rate | <5% escape rate | 0% (Phase 1) |

---

## Phase Breakdown

### Phase 1: Storage Foundation ✅ COMPLETE

**Duration**: 2 days (Jan 29-31, 2026)  
**Status**: ✅ Complete  
**LOC**: 1,169 (386 core + 457 turso + 326 redb)  
**Tests**: 11 (100% passing)

#### Deliverables
- ✅ RelationshipType enum (7 variants)
- ✅ EpisodeRelationship struct
- ✅ RelationshipMetadata struct
- ✅ Direction enum
- ✅ Database schema with 4 indexes
- ✅ Turso storage layer (7 methods)
- ✅ Redb cache layer (6 methods)
- ✅ Comprehensive test suite

#### Key Files
- `do-memory-core/src/episode/relationships.rs`
- `do-memory-storage-turso/src/relationships.rs`
- `do-memory-storage-redb/src/relationships.rs`
- `do-memory-storage-turso/src/schema.rs`

#### Lessons Learned
- Postcard serialization performs well for cache
- UNIQUE constraints prevent duplicate relationships effectively
- CASCADE deletes simplify cleanup logic
- Comprehensive indexing critical for query performance

---

### Phase 2: Core API & Business Logic ⏳ PLANNED

**Duration**: 2-3 days  
**Status**: Not Started  
**Estimated LOC**: ~800  
**Estimated Tests**: 20+  
**Target Coverage**: >90%

#### Objectives
1. Implement relationship validation rules
2. Build graph algorithms for cycle detection
3. Create high-level relationship manager API
4. Ensure data integrity and correctness

#### Deliverables
- [ ] `RelationshipManager` struct with in-memory graph
- [ ] Validation: prevent self-relationships
- [ ] Validation: prevent duplicates
- [ ] Validation: cycle detection (DFS-based)
- [ ] Validation: priority range (1-10)
- [ ] Graph algorithm: has_path()
- [ ] Graph algorithm: find_path()
- [ ] Graph algorithm: has_cycle()
- [ ] Graph algorithm: topological_sort()
- [ ] Graph algorithm: transitive_closure()
- [ ] Error types: ValidationError, RemovalError, GraphError
- [ ] 20+ unit tests

#### Key Files (New)
- `do-memory-core/src/episode/relationship_manager.rs` (~400 LOC)
- `do-memory-core/src/episode/graph_algorithms.rs` (~400 LOC)

#### Dependencies
- Phase 1: Complete ✅

#### Risk Assessment
- **High Risk**: Graph algorithm correctness (requires thorough testing)
- **Medium Risk**: Performance at scale (may need optimization)
- **Mitigation**: Use proven algorithms, extensive unit tests, early benchmarking

#### Acceptance Criteria
- [ ] All validation rules implemented and tested
- [ ] Cycle detection works for graphs up to 1000 nodes
- [ ] Topological sort produces correct ordering
- [ ] All 20+ tests passing
- [ ] Zero clippy warnings
- [ ] >90% code coverage

---

### Phase 3: Memory Layer Integration ⏳ PLANNED

**Duration**: 2 days  
**Status**: Not Started  
**Estimated LOC**: ~400  
**Estimated Tests**: 15+  
**Target Coverage**: >90%

#### Objectives
1. Extend MemoryManager with relationship methods
2. Integrate validation with storage operations
3. Implement cache-aware queries
4. Add relationship-based filtering

#### Deliverables
- [ ] `MemoryManager::add_episode_relationship()` - Public API
- [ ] `MemoryManager::remove_episode_relationship()` - Public API
- [ ] `MemoryManager::get_episode_relationships()` - With caching
- [ ] `MemoryManager::find_related_episodes()` - With filtering
- [ ] `MemoryManager::get_relationship_graph()` - Export graph
- [ ] `RelationshipFilter` struct for advanced queries
- [ ] `RelationshipGraph` struct for visualization
- [ ] Cache warming strategy
- [ ] Cache invalidation on updates
- [ ] 15+ integration tests

#### Key Files (Modified/New)
- `do-memory-core/src/memory/mod.rs` (extend existing)
- `do-memory-core/src/memory/query.rs` (new or extend)

#### Dependencies
- Phase 1: Complete ✅
- Phase 2: Required (for validation logic)

#### Risk Assessment
- **Medium Risk**: Cache consistency across layers
- **Low Risk**: Integration complexity (patterns established)
- **Mitigation**: Write-through caching, explicit invalidation

#### Acceptance Criteria
- [ ] All MemoryManager methods work end-to-end
- [ ] Cache hit rate >80% in tests
- [ ] Cycle detection integrated with storage
- [ ] All 15+ tests passing
- [ ] No cache inconsistencies observed

---

### Phase 4: MCP Server Tools ⏳ PLANNED

**Duration**: 2-3 days  
**Status**: Not Started  
**Estimated LOC**: ~600  
**Estimated Tests**: 16+  
**Target Coverage**: >90%

#### Objectives
1. Expose relationship operations via MCP protocol
2. Implement JSON-RPC schemas
3. Add error handling and validation
4. Enable programmatic access for AI agents

#### Deliverables
- [ ] `add_episode_relationship` - Create relationship
- [ ] `remove_episode_relationship` - Delete relationship
- [ ] `get_episode_relationships` - Query relationships
- [ ] `find_related_episodes` - Find related episodes
- [ ] `check_relationship_exists` - Existence check
- [ ] `get_dependency_graph` - Export graph structure
- [ ] `validate_no_cycles` - Pre-flight validation
- [ ] `get_topological_order` - Ordered list
- [ ] JSON-RPC schemas for all 8 tools
- [ ] Error response handling
- [ ] 16+ tool tests (2 per tool)

#### Key Files (Modified)
- `do-memory-mcp/src/bin/server/handlers.rs` (add 8 handlers)
- `do-memory-mcp/src/bin/server/jsonrpc.rs` (extend schemas)

#### Dependencies
- Phase 1: Complete ✅
- Phase 2: Required (for validation)
- Phase 3: Required (for MemoryManager API)

#### Risk Assessment
- **Medium Risk**: JSON-RPC protocol compliance
- **Low Risk**: Implementation (follows existing patterns)
- **Mitigation**: Follow existing tool patterns, comprehensive tests

#### Acceptance Criteria
- [ ] All 8 MCP tools implemented
- [ ] JSON-RPC 2.0 compliant
- [ ] Error responses follow spec
- [ ] All 16+ tests passing
- [ ] Tool response time <100ms (P95)

---

### Phase 5: CLI Commands ⏳ PLANNED

**Duration**: 2 days  
**Status**: Not Started  
**Estimated LOC**: ~500  
**Estimated Tests**: 14+  
**Target Coverage**: >90%

#### Objectives
1. Add CLI commands for relationship management
2. Implement multiple output formats (table, JSON, DOT)
3. Provide user-friendly interface
4. Enable shell scripting

#### Deliverables
- [ ] `episode add-relationship` - Create relationship
- [ ] `episode remove-relationship` - Delete relationship
- [ ] `episode list-relationships` - List with filters
- [ ] `episode find-related` - Find related episodes
- [ ] `episode dependency-graph` - Export graph
- [ ] `episode validate-cycles` - Check for cycles
- [ ] `episode topological-sort` - Sort episodes
- [ ] Table output formatting
- [ ] JSON output formatting
- [ ] DOT graph export
- [ ] ASCII tree visualization
- [ ] 14+ CLI tests (2 per command)

#### Key Files (New)
- `do-memory-cli/src/commands/episode_v2/relationships.rs` (~500 LOC)

#### Dependencies
- Phase 1: Complete ✅
- Phase 2: Required (for validation)
- Phase 3: Required (for MemoryManager API)

#### Risk Assessment
- **Medium Risk**: CLI UX design (needs user feedback)
- **Low Risk**: Implementation (established patterns)
- **Mitigation**: Follow existing CLI patterns, user testing

#### Acceptance Criteria
- [ ] All 7 CLI commands implemented
- [ ] Help documentation complete
- [ ] Output formats work correctly
- [ ] All 14+ tests passing
- [ ] Command execution <200ms (P95)

---

### Phase 6: Testing & Documentation ⏳ PLANNED

**Duration**: 2 days  
**Status**: Not Started  
**Estimated LOC**: ~300  
**Estimated Tests**: 25+  
**Target Coverage**: >95%

#### Objectives
1. Write comprehensive integration tests
2. Implement performance benchmarks
3. Complete documentation
4. Ensure production readiness

#### Deliverables
- [ ] 10 end-to-end workflow tests
- [ ] 15 performance benchmarks
- [ ] User guide with examples
- [ ] API documentation (rustdoc)
- [ ] Architecture decision records
- [ ] Migration guide (if needed)
- [ ] Performance test report
- [ ] Feature documentation update

#### Key Files (New/Modified)
- `tests/integration/relationships.rs` (new)
- `benches/relationships.rs` (new)
- `docs/EPISODE_RELATIONSHIPS.md` (new)
- `plans/RELATIONSHIP_MODULE.md` (update)

#### Dependencies
- All Phases 1-5 complete

#### Risk Assessment
- **Low Risk**: Testing well-understood
- **Low Risk**: Documentation straightforward
- **Mitigation**: Follow existing patterns

#### Acceptance Criteria
- [ ] All E2E tests passing
- [ ] Overall coverage >92%
- [ ] All performance targets met
- [ ] Documentation complete
- [ ] User guide reviewed
- [ ] Zero known bugs

---

## Timeline Overview

### Optimistic (9 days)

```
Week 1: Jan 29 - Feb 4
├─ Phase 1: ✅ Complete (2 days)
├─ Phase 2: Days 3-4 (2 days)
└─ Phase 3: Days 5-6 (2 days)

Week 2: Feb 5 - Feb 11
├─ Phase 4: Days 7-8 (2 days, parallel with Phase 5)
├─ Phase 5: Days 7-8 (2 days, parallel with Phase 4)
└─ Phase 6: Day 9 (1 day)
```

**Total**: 9 days

### Realistic (12 days)

```
Week 1: Jan 29 - Feb 4
├─ Phase 1: ✅ Complete (2 days)
├─ Phase 2: Days 3-5 (3 days - graph algorithms complex)
└─ Phase 3: Days 6-7 (2 days)

Week 2: Feb 8 - Feb 14
├─ Phase 4: Days 8-10 (3 days)
├─ Phase 5: Days 11-12 (2 days)
└─ Phase 6: Days 13-14 (2 days)
```

**Total**: 12 days ⭐ **RECOMMENDED**

### Conservative (15 days)

```
Week 1: Jan 29 - Feb 4
├─ Phase 1: ✅ Complete (2 days)
├─ Phase 2: Days 3-6 (4 days - includes buffer)
└─ Phase 3: Days 7-9 (3 days - includes buffer)

Week 2: Feb 10 - Feb 18
├─ Phase 4: Days 10-13 (4 days - includes buffer)
├─ Phase 5: Days 14-16 (3 days - includes buffer)
└─ Phase 6: Days 17-18 (2 days)
```

**Total**: 15 days (with buffers)

---

## Resource Allocation

### Single Developer
- **Timeline**: 12-15 days (sequential)
- **Risk**: Slower delivery, single point of failure
- **Recommendation**: Use for Phases 1-3, parallelize 4-5

### Two Developers
- **Timeline**: 8-10 days (Phases 4-5 parallel)
- **Risk**: Communication overhead
- **Recommendation**: ⭐ **OPTIMAL**
  - Developer A: Phases 2, 3, 4 (MCP)
  - Developer B: Phase 5 (CLI), Phase 6 (testing)

### Three Developers
- **Timeline**: 7-9 days (maximum parallelization)
- **Risk**: Coordination complexity
- **Recommendation**: Only if deadline critical
  - Developer A: Phases 2-3
  - Developer B: Phase 4 (MCP)
  - Developer C: Phase 5 (CLI) + Phase 6

---

## Risk Management

### High Priority Risks

| Risk | Impact | Probability | Mitigation |
|------|--------|-------------|------------|
| Graph algorithm bugs | High | Medium | Extensive unit tests, use proven algorithms |
| Performance at scale | High | Low | Early benchmarking, optimization in Phase 6 |
| Cycle detection edge cases | Medium | Medium | Comprehensive test cases, formal verification |

### Medium Priority Risks

| Risk | Impact | Probability | Mitigation |
|------|--------|-------------|------------|
| Cache consistency | Medium | Low | Write-through strategy, explicit invalidation |
| MCP protocol changes | Medium | Low | Follow spec closely, integration tests |
| CLI UX issues | Medium | Medium | User testing, feedback iteration |

### Low Priority Risks

| Risk | Impact | Probability | Mitigation |
|------|--------|-------------|------------|
| Database migration | Low | Low | Schema already created in Phase 1 |
| Documentation gaps | Low | Low | Phase 6 dedicated to documentation |
| Test flakiness | Low | Low | Deterministic tests, proper fixtures |

---

## Quality Gates

### Phase Completion Criteria

Each phase must meet:
- ✅ All deliverables complete
- ✅ All tests passing
- ✅ Coverage targets met (>90%)
- ✅ Zero clippy warnings
- ✅ Code review approved
- ✅ Documentation updated

### Feature Completion Criteria

Overall feature must meet:
- ✅ All 6 phases complete
- ✅ 116+ tests passing
- ✅ >92% overall coverage
- ✅ Performance targets met
- ✅ User acceptance testing passed
- ✅ Production deployment successful
- ✅ Zero critical bugs in first month

---

## Performance Targets

| Operation | Phase | Target (P95) |
|-----------|-------|--------------|
| add_relationship (storage) | 1 | <10ms ✅ |
| get_relationships (storage) | 1 | <20ms ✅ |
| add_with_validation | 2 | <5ms |
| has_cycle | 2 | <20ms (1000 nodes) |
| topological_sort | 2 | <50ms (1000 nodes) |
| MemoryManager::add_relationship | 3 | <50ms |
| MemoryManager::find_related | 3 | <100ms |
| MCP tool call | 4 | <100ms |
| CLI command | 5 | <200ms |
| Graph export (500 nodes) | 5 | <500ms |

---

## Success Metrics

### Technical Metrics

- **Test Coverage**: >92% (currently 100% for Phase 1)
- **Performance**: All targets met
- **Bug Density**: <1 bug per 1000 LOC
- **Code Quality**: Zero clippy warnings
- **Documentation**: 100% public APIs documented

### User Metrics (Post-Release)

- **Adoption Rate**: >50% of episode workflows use relationships
- **User Satisfaction**: >4/5 rating
- **Support Tickets**: <5 relationship-related tickets per month
- **Feature Requests**: Track for future enhancements

### Business Metrics

- **Time to Complete**: Within 12-15 days
- **Code Maintainability**: <500 LOC per file (all compliant)
- **Technical Debt**: Zero known shortcuts taken
- **Reusability**: Patterns reused in future features

---

## Post-Launch Plan

### Week 1 Post-Launch
- Monitor error rates
- Collect user feedback
- Fix critical bugs (P0/P1)
- Performance tuning if needed

### Week 2-4 Post-Launch
- Address user feedback
- Fix medium priority bugs (P2)
- Add missing documentation
- Plan enhancements

### Month 2+
- Feature enhancements based on usage
- Performance optimizations
- Advanced graph algorithms (if needed)
- Integration with other features

---

## Future Enhancements (Beyond Phase 6)

### V2 Features (Potential)
1. **Visual Graph Editor**: Web UI for relationship management
2. **Automatic Relationship Discovery**: ML-based relationship suggestions
3. **Workflow Templates**: Pre-defined relationship patterns
4. **Relationship History**: Track changes over time
5. **Advanced Analytics**: Graph metrics (centrality, clustering, etc.)
6. **Relationship Permissions**: Fine-grained access control
7. **Bulk Operations**: Import/export relationships
8. **Relationship Webhooks**: Notify on relationship changes

### Integration Opportunities
- **Project Management**: Integrate with Jira, GitHub Issues
- **Visualization**: Export to Mermaid, Graphviz
- **Analytics**: Feed into learning algorithms
- **Reporting**: Generate dependency reports

---

## Communication Plan

### Weekly Status Updates

**Format**: Email to stakeholders

**Content**:
- Phase completion status
- Blockers and risks
- Next week's goals
- Metrics update

### Phase Completion Demos

**Audience**: Team + stakeholders

**Content**:
- Live demo of new functionality
- Test results and coverage
- Performance metrics
- Q&A

### Documentation Updates

**Frequency**: Continuous (per phase)

**Locations**:
- `plans/EPISODE_RELATIONSHIPS_IMPLEMENTATION_STATUS.md`
- `plans/RELATIONSHIP_MODULE.md`
- GitHub release notes

---

## Conclusion

The Episode Relationships feature is **20% complete** with Phase 1 successfully delivered. The remaining 5 phases are well-planned and ready for implementation.

**Recommended Next Steps**:
1. ✅ Begin Phase 2 implementation (graph algorithms)
2. ✅ Assign resources (1-2 developers)
3. ✅ Set up CI/CD for relationship tests
4. ✅ Schedule weekly status reviews

**Estimated Completion**: February 14, 2026 (12 days from Phase 1 completion)

**Confidence Level**: High (Phase 1 complete, patterns established, dependencies clear)

---

## References

- **Implementation Status**: `plans/EPISODE_RELATIONSHIPS_IMPLEMENTATION_STATUS.md`
- **Phase 2 Plan**: `plans/EPISODE_RELATIONSHIPS_PHASE2_PLAN.md`
- **Phase 3 Plan**: `plans/EPISODE_RELATIONSHIPS_PHASE3_PLAN.md`
- **Phase 4-5 Plan**: `plans/EPISODE_RELATIONSHIPS_PHASE4_5_PLAN.md`
- **Testing Strategy**: `plans/EPISODE_RELATIONSHIPS_TESTING_STRATEGY.md`
- **Feature Documentation**: `plans/RELATIONSHIP_MODULE.md`

---

**Status**: Ready for Phase 2 implementation  
**Last Updated**: 2026-01-31  
**Next Review**: 2026-02-03 (after Phase 2 completion)
