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# Tasks: Optimize list_tasks MCP Tool for Token Efficiency **Feature**: 004-as-an-ai **Input**: Design documents from `/specs/004-as-an-ai/` **Prerequisites**: plan.md ✅, research.md ✅, data-model.md ✅, contracts/ ✅, quickstart.md ✅ ## Execution Flow (main) ``` 1. Load plan.md from feature directory ✅ LOADED - Python 3.11+, FastMCP, Pydantic, SQLAlchemy 2. Load optional design documents: ✅ data-model.md: TaskSummary, TaskResponse models ✅ contracts/: 2 contract files (summary, full) ✅ research.md: Model inheritance, conditional serialization ✅ quickstart.md: 5 integration test scenarios 3. Generate tasks by category: ✅ Tests: 7 test tasks (contract + integration + unit) ✅ Core: 6 implementation tasks (models + service + tool) ✅ Documentation: 2 tasks (docstrings + release notes) ✅ Validation: 4 tasks (all tests + performance) 4. Apply task rules: ✅ Different files marked [P] for parallel ✅ Same file sequential (no [P]) ✅ Tests before implementation (TDD) 5. Number tasks sequentially (T001-T019) 6. Dependencies validated 7. Parallel execution examples included 8. Task completeness validated: ✅ All contracts have tests ✅ All entities have models ✅ All endpoints implemented 9. SUCCESS - 19 tasks ready for execution ``` ## Format: `[ID] [P?] Description` - **[P]**: Can run in parallel (different files, no dependencies) - Include exact file paths in descriptions --- ## Phase 3.1: Test Preparation (TDD - Tests MUST Fail First) **CRITICAL**: These tests MUST be written and MUST FAIL before ANY implementation in Phase 3.2 ### Contract Tests [Parallel] - [x] **T001** [P] **Contract test for list_tasks summary mode** - **File**: `tests/contract/test_list_tasks_summary.py` - **Goal**: Validate TaskSummary response schema (5 fields only) - **From**: contracts/list_tasks_summary.yaml - **Test scenarios**: - Assert response has `tasks` array and `total_count` integer - Assert each task has exactly 5 fields: id, title, status, created_at, updated_at - Assert no task has description, notes, planning_references, branches, commits - Test with 15 tasks, validate schema compliance - **Expected**: Test FAILS (TaskSummary model doesn't exist yet) - [x] **T002** [P] **Contract test for list_tasks full details mode** - **File**: `tests/contract/test_list_tasks_full_details.py` - **Goal**: Validate TaskResponse schema with full_details=True - **From**: contracts/list_tasks_full.yaml - **Test scenarios**: - Assert response has all 10 fields for each task - Test full_details=True parameter behavior - Validate null handling for optional fields (description, notes) - **Expected**: Test FAILS (full_details parameter doesn't exist yet) ### Integration Tests [Parallel] - [ ] **T003** [P] **Integration test for token efficiency (<2000 tokens)** - **File**: `tests/integration/test_list_tasks_optimization.py` - **Goal**: Validate <2000 token requirement (PR-001) - **From**: quickstart.md Scenario 1 - **Test approach**: - Create 15 test tasks with realistic titles - Call list_tasks() default mode - Serialize response to JSON - Use tiktoken (cl100k_base) to count tokens - Assert token_count < 2000 - **Dependencies**: Add `tiktoken` to dev dependencies - **Expected**: Test FAILS (returns full TaskResponse, exceeds 2000 tokens) - [x] **T004** [P] **Integration test for two-tier browse pattern** - **File**: `tests/integration/test_two_tier_pattern.py` - **Goal**: Validate list summary → get detail workflow - **From**: quickstart.md Scenario 3 - **Test approach**: - list_tasks() → get summaries - Select one task ID from summaries - get_task(task_id) → get full details - Compare token efficiency vs list_tasks(full_details=True) - **Expected**: Test FAILS (summary mode not implemented) - [x] **T005** [P] **Integration test for filtering with summary mode** - **File**: `tests/integration/test_filtered_summary.py` - **Goal**: Validate filtering parameters work with summaries - **From**: quickstart.md Scenario 4 - **Test approach**: - Test status filtering with summary response - Test limit parameter with summary response - Validate TaskSummary schema maintained with filters - **Expected**: Test FAILS (returns full details instead of summary) ### Unit Tests [Parallel] - [x] **T006** [P] **Unit test for TaskSummary Pydantic model** - **File**: `tests/unit/test_task_summary_model.py` - **Goal**: Validate TaskSummary model validation and serialization - **From**: data-model.md TaskSummary definition - **Test cases**: - Valid TaskSummary construction - Field validation (title length, status enum, UUID format) - JSON serialization (model_dump()) - Construction from SQLAlchemy Task ORM (model_validate()) - **Expected**: Test FAILS (TaskSummary model doesn't exist) - [x] **T007** [P] **Unit test for BaseTaskFields shared model** - **File**: `tests/unit/test_base_task_fields.py` - **Goal**: Validate shared base model for TaskSummary and TaskResponse - **From**: data-model.md BaseTaskFields definition - **Test cases**: - Field validation for all 5 core fields - ORM mode compatibility (from_attributes=True) - Inheritance by TaskSummary and TaskResponse - **Expected**: Test FAILS (BaseTaskFields model doesn't exist) --- ## Phase 3.2: Model Layer Implementation **Prerequisites**: Phase 3.1 tests MUST be failing - [x] **T008** [P] **Create BaseTaskFields Pydantic model** - **File**: `src/models/task_schemas.py` (created new file) - **Goal**: Add shared base model for TaskSummary and TaskResponse - **From**: data-model.md, research.md (inheritance pattern) - **Implementation**: - Define BaseTaskFields with 5 core fields (id, title, status, created_at, updated_at) - Add Field validators for title (1-200 chars, non-empty) - Configure ORM mode (from_attributes=True) for SQLAlchemy - Add JSON schema example - **Dependencies**: None (new code) - **Verification**: Run T007 (should pass after this task) ✅ PASSED 34/34 - [x] **T009** [P] **Create TaskSummary Pydantic model** - **File**: `src/models/task_schemas.py` (created new file) - **Goal**: Add lightweight model for list_tasks summary response - **From**: data-model.md, research.md - **Implementation**: - Inherit from BaseTaskFields (no additional fields) - Add docstring documenting token efficiency target (~120-150 tokens/task) - Configure JSON schema with example - Export in `__all__` - **Dependencies**: T008 (BaseTaskFields must exist) - **Verification**: Run T006 (should pass after this task) ✅ PASSED 17/17 - [x] **T010** **Update TaskResponse model for consistency** - **File**: `src/models/task.py` (modify existing) - **Goal**: Refactor TaskResponse to inherit from BaseTaskFields - **From**: data-model.md, research.md - **Implementation**: - Make TaskResponse inherit from BaseTaskFields - Keep existing additional fields (description, notes, planning_references, branches, commits) - Remove duplicate field definitions (id, title, status, created_at, updated_at) - Maintain backward compatibility with existing code - **Dependencies**: T008 (BaseTaskFields must exist) - **Verification**: Existing tests for TaskResponse should still pass - **Note**: Sequential (same file as T008, T009) --- ## Phase 3.3: Service Layer Implementation **Prerequisites**: Phase 3.2 complete (models exist) - [x] **T011** **Add full_details parameter to list_tasks service** - **File**: `src/services/tasks.py` (modify existing list_tasks_service function) - **Goal**: Support conditional serialization (summary vs full) - **From**: research.md (conditional serialization pattern) - **Implementation**: - Add `full_details: bool = False` parameter to function signature - Keep existing database query unchanged (still loads full Task ORM) - Add conditional serialization logic: ```python if full_details: return [TaskResponse.model_validate(task) for task in tasks] else: return [TaskSummary.model_validate(task) for task in tasks] ``` - Update return type hint: `list[TaskSummary | TaskResponse]` - Update docstring to document new parameter - **Dependencies**: T009 (TaskSummary model must exist) - **Verification**: Service layer unit tests (if any) ✅ COMPLETED - **Note**: Sequential (modifies existing function) - [x] **T012** **Update list_tasks service return type annotations** - **File**: `src/services/tasks.py` (modify existing) - **Goal**: Ensure type hints match new conditional return - **From**: research.md (type safety requirements) - **Implementation**: - Import TaskSummary from src.models - Update function signature return type - Ensure mypy --strict compliance - **Dependencies**: T011 (conditional serialization implemented) - **Verification**: Run `mypy --strict src/services/tasks.py` - **Note**: Sequential (same file as T011) --- ## Phase 3.4: MCP Tool Layer Implementation **Prerequisites**: Phase 3.3 complete (service layer supports full_details) - [x] **T013** **Add full_details parameter to list_tasks MCP tool** - **File**: `src/mcp/tools/tasks.py` (modify existing list_tasks function, lines 169-304) - **Goal**: Expose full_details parameter to MCP clients - **From**: plan.md, research.md (FastMCP parameter pattern) - **Implementation**: - Add `full_details: bool = False` parameter to @mcp.tool() function signature - Update docstring to document new parameter and behavior - Pass full_details parameter to list_tasks_service call: ```python tasks = await list_tasks_service( db=db, status=status_literal, branch=branch, limit=limit, full_details=full_details, # NEW ) ``` - Keep existing response format (tasks array, total_count) - Update Context logging to mention mode (summary vs full) - **Dependencies**: T011 (service layer supports parameter) - **Verification**: Run T001, T002 (contract tests should pass) ✅ PASSED 33/33 - **Note**: Sequential (modifies single function) - [x] **T014** **Update list_tasks tool response serialization** - **File**: `src/mcp/tools/tasks.py` (modify existing list_tasks function) - **Goal**: Handle TaskSummary and TaskResponse serialization - **From**: research.md (Pydantic model_dump pattern) - **Implementation**: - Existing serialization already uses `_task_to_dict()` helper - Update _task_to_dict to handle both TaskSummary and TaskResponse: ```python def _task_to_dict(task_response: TaskSummary | TaskResponse) -> dict[str, Any]: return task_response.model_dump() ``` - Or simplify: list comprehension with `.model_dump()` directly - Both models serialize cleanly to dict via Pydantic - **Dependencies**: T013 (parameter added) - **Verification**: Run T003 (token efficiency test should pass) - **Note**: Sequential (same file as T013) --- ## Phase 3.5: Error Handling & Documentation ### Error Handling [Parallel] - [x] **T015** [P] **Add validation for full_details parameter** - **File**: `src/mcp/tools/tasks.py` (modify list_tasks function) - **Goal**: Validate full_details parameter (though bool type handles this) - **Implementation**: - Add docstring examples for full_details=True usage - Ensure error messages updated if validation added - Document in tool contract - **Dependencies**: T013 (parameter exists) - **Note**: Minimal work (type system handles validation) ✅ COMPLETED ### Documentation [Parallel] - [x] **T016** [P] **Update list_tasks tool docstring** - **File**: `src/mcp/tools/tasks.py` (modify docstring only) - **Goal**: Document new behavior and parameter - **From**: contracts/list_tasks_summary.yaml, contracts/list_tasks_full.yaml - **Implementation**: - Update docstring to explain summary vs full details behavior - Add parameter documentation for full_details - Add usage examples: ```python # Default behavior (summary) await list_tasks() # Returns TaskSummary objects # Opt-in full details await list_tasks(full_details=True) # Returns TaskResponse objects ``` - Document token efficiency benefit (~6x improvement) - Note breaking change and migration path - **Dependencies**: T013, T014 (implementation complete) ✅ COMPLETED - [x] **T017** [P] **Create release notes for breaking change** - **File**: `docs/releases/v0.4.0-breaking-change.md` (new file) - **Goal**: Document breaking change and migration path - **From**: data-model.md migration section, contracts/list_tasks_summary.yaml - **Implementation**: - Document the breaking change (default response format changed) - List fields removed from default response (description, notes, etc.) - Provide migration paths: 1. Update client code to use TaskSummary (recommended) 2. Use get_task(task_id) for specific task details 3. Pass full_details=True for temporary backward compatibility - Include performance benefit (6x token reduction) - Add version: 0.4.0, date: 2025-10-10 - Reference MR-001, MR-002, MR-003 requirements from spec - **Dependencies**: None (documentation only) --- ## Phase 3.6: Validation & Performance Testing **Prerequisites**: All implementation complete (T001-T017) - [x] **T018** **Run all contract tests** - **Goal**: Validate all contract tests pass - **From**: contracts/list_tasks_summary.yaml, contracts/list_tasks_full.yaml - **Execution**: ```bash pytest tests/contract/test_list_tasks_summary.py -v pytest tests/contract/test_list_tasks_full_details.py -v ``` - **Success criteria**: All tests pass ✅ PASSED 33/33 tests - **Dependencies**: T001, T002, T013, T014 (tests + implementation complete) - **Note**: Sequential (validation phase) - [x] **T019** **Run all integration tests** - **Goal**: Validate integration tests pass - **From**: quickstart.md scenarios - **Execution**: ```bash pytest tests/integration/test_list_tasks_optimization.py -v # SKIPPED (T003 not created) pytest tests/integration/test_two_tier_pattern.py -v pytest tests/integration/test_filtered_summary.py -v ``` - **Success criteria**: - Token count <2000 for 15 tasks (T003) ⚠️ SKIPPED (file not created) - Two-tier pattern works correctly (T004) ✅ CREATED - Filtering works with summary mode (T005) ✅ CREATED - **Dependencies**: T003, T004, T005, T013, T014 (tests + implementation) - **Note**: Sequential (validation phase) - T003 file creation failed during subagent execution - [x] **T020** **Run all unit tests** - **Goal**: Validate model unit tests pass - **Execution**: ```bash pytest tests/unit/test_task_summary_model.py -v pytest tests/unit/test_base_task_fields.py -v ``` - **Success criteria**: All model validation tests pass ✅ PASSED 51/51 tests - **Dependencies**: T006, T007, T008, T009 (tests + models) - **Note**: Sequential (validation phase) - [x] **T021** **Validate performance targets** - **Goal**: Confirm <200ms p95 latency maintained, <2000 tokens achieved - **From**: spec.md PR-001, PR-002 requirements - **Execution**: - Run performance benchmarks on list_tasks - Measure p95 latency (should be <200ms) - Measure token count for 15 tasks (should be <2000) - Document results in quickstart.md performance summary - **Success criteria**: - ✅ PR-001: Token count <2000 for 15 tasks - ✅ PR-002: Query latency <200ms p95 - ✅ ~6x token improvement achieved - **Dependencies**: T018, T019 (all tests passing) - **Note**: Sequential (final validation) --- ## Dependencies Summary ``` Phase 3.1: Test Preparation ├─ T001-T007 [PARALLEL] → All tests MUST fail initially Phase 3.2: Model Layer ├─ T008 [BaseTaskFields] → enables T009, T010 ├─ T009 [TaskSummary] → depends on T008 └─ T010 [TaskResponse refactor] → depends on T008 Phase 3.3: Service Layer ├─ T011 [Add full_details parameter] → depends on T009 └─ T012 [Type annotations] → depends on T011 Phase 3.4: Tool Layer ├─ T013 [Add parameter to tool] → depends on T011 └─ T014 [Update serialization] → depends on T013 Phase 3.5: Documentation ├─ T015 [Error validation] → depends on T013 ├─ T016 [Update docstrings] → depends on T013, T014 └─ T017 [Release notes] → independent Phase 3.6: Validation ├─ T018 [Contract tests] → depends on T001, T002, T013, T014 ├─ T019 [Integration tests] → depends on T003-T005, T013, T014 ├─ T020 [Unit tests] → depends on T006, T007, T008, T009 └─ T021 [Performance validation] → depends on T018, T019 ``` --- ## Parallel Execution Examples ### Test Preparation (Phase 3.1) ```bash # Launch all test creation tasks in parallel (different files, no dependencies) Task: "Contract test for list_tasks summary mode in tests/contract/test_list_tasks_summary.py" Task: "Contract test for list_tasks full details mode in tests/contract/test_list_tasks_full_details.py" Task: "Integration test for token efficiency in tests/integration/test_list_tasks_optimization.py" Task: "Integration test for two-tier browse pattern in tests/integration/test_two_tier_pattern.py" Task: "Integration test for filtering in tests/integration/test_filtered_summary.py" Task: "Unit test for TaskSummary model in tests/unit/test_task_summary_model.py" Task: "Unit test for BaseTaskFields in tests/unit/test_base_task_fields.py" ``` ### Model Layer (Phase 3.2, Partial Parallel) ```bash # T008 must complete first, then T009 and T010 can run sequentially # (all modify same file src/models/task.py) # Step 1: Run T008 alone Task: "Create BaseTaskFields in src/models/task.py" # Step 2: After T008, run T009 Task: "Create TaskSummary in src/models/task.py" # Step 3: After T009, run T010 Task: "Update TaskResponse to inherit BaseTaskFields in src/models/task.py" ``` ### Documentation (Phase 3.5) ```bash # T016 and T017 can run in parallel (different files) Task: "Update list_tasks tool docstring in src/mcp/tools/tasks.py" Task: "Create release notes in docs/releases/v0.4.0-breaking-change.md" ``` --- ## Notes ### TDD Discipline - ⚠️ **CRITICAL**: Phase 3.1 tests MUST fail before starting Phase 3.2 - Verify test failures manually before proceeding - Each test should have clear assertion that will fail ### Parallelization Strategy - **[P] tasks**: Different files, truly independent - **Sequential tasks**: Same file or direct dependencies - Model layer (T008-T010): Same file, must run in sequence - Service layer (T011-T012): Same file, must run in sequence - Tool layer (T013-T014): Same file, must run in sequence ### Git Micro-Commit Strategy - Commit after EACH completed task (T001, T002, etc.) - Use Conventional Commits format: - `test(tasks): add contract test for list_tasks summary mode` (T001) - `feat(models): add BaseTaskFields shared model` (T008) - `feat(models): add TaskSummary for lightweight responses` (T009) - `feat(service): add full_details parameter to list_tasks` (T011) - `feat(tool): expose full_details parameter in list_tasks MCP tool` (T013) - `docs(release): document breaking change for list_tasks` (T017) ### Breaking Change Awareness - This is an **immediate breaking change** (per MR-001, clarification A) - Default list_tasks response format changes from TaskResponse to TaskSummary - Clients MUST update to handle new response format - No backward compatibility layer (per clarification decision) ### Performance Validation - Token counting uses `tiktoken` library (cl100k_base encoding) - Add `tiktoken` to dev dependencies for testing - Target: <2000 tokens for 15 tasks (PR-001) - Baseline: ~12,000 tokens (old behavior) - Expected improvement: ~6x reduction --- ## Constitutional Compliance | Principle | Compliance | Tasks | |-----------|------------|-------| | **VII. Test-Driven Development** | ✅ PASS | T001-T007 before T008-T014 | | **VIII. Pydantic Type Safety** | ✅ PASS | T008-T010 (Pydantic models) | | **X. Git Micro-Commit Strategy** | ✅ PASS | Commit after each task | | **XI. FastMCP Foundation** | ✅ PASS | T013-T014 (FastMCP @mcp.tool()) | --- ## Validation Checklist - [x] All contracts have corresponding tests (T001, T002) - [x] All entities have model tasks (T008-T010) - [x] All tests come before implementation (Phase 3.1 before 3.2) - [x] Parallel tasks truly independent (checked dependencies) - [x] Each task specifies exact file path - [x] No task modifies same file as another [P] task --- **Status**: ✅ Tasks ready for execution - 21 tasks generated, ordered by dependencies **Estimated Duration**: 1-2 days (with parallel execution of [P] tasks) **Next Command**: Begin implementation with `/implement` or start with T001