ai-agent-tdd-skill

JSON Tracker Schema

The tracker file is the single source of truth for feature implementation progress. It is a local working file - not committed to version control.

Schema

{
  "phase": "Human-readable phase/feature name",
  "issue": "GitHub/GitLab issue reference (e.g., org/repo#76)",
  "design_doc": "path/to/design-doc.md (optional)",
  "plan_doc": "path/to/plan.md (optional)",
  "chunks": [
    {
      "id": 1,
      "name": "Short descriptive name",
      "status": "pending",
      "files_create": ["path/to/NewFile.ext"],
      "files_modify": ["path/to/ExistingFile.ext"],
      "test_files": ["path/to/TestFile.ext"],
      "acceptance_criteria": ["Criterion 1", "Criterion 2"],
      "tdd": "Write test for X. Run -> fail -> implement -> pass.",
      "depends_on": [],
      "resume": "Compact implementation instructions for session resumption.",
      "notes": "Optional notes about decisions or constraints."
    }
  ],
  "quality_verification": {
    "completeness": "Summary of completeness check",
    "correctness": "Summary of correctness check",
    "gaps_functional": "Summary of functional gaps check",
    "standards": "Summary of standards check",
    "regression": "Summary of regression check",
    "robustness": "Summary of robustness check",
    "gaps_architectural": "Summary of architectural gaps check",
    "blindspots": "Summary of blindspots check"
  }
}

Field Definitions

Top-level Fields

Field	Required	Description
`phase`	Yes	Human-readable name for the feature or phase
`issue`	Yes	Issue tracker reference
`design_doc`	No	Path to design document
`plan_doc`	No	Path to plan document
`chunks`	Yes	Array of implementation chunks
`quality_verification`	No	Filled after all chunks complete

Chunk Fields

Field	Required	Description
`id`	Yes	Integer, sequential starting at 1
`name`	Yes	Short descriptive name (5-10 words)
`status`	Yes	`pending`, `in_progress`, `complete`, or `error`
`files_create`	Yes	Paths of new files to create (empty array if none)
`files_modify`	Yes	Paths of existing files to modify (empty array if none)
`test_files`	Yes	Paths of test files (new or modified)
`acceptance_criteria`	Yes	Array of testable pass/fail conditions for this chunk
`tdd`	Yes	TDD instructions: what to test, expected fail, then pass
`depends_on`	Yes	Array of chunk IDs that must be `complete` first
`resume`	Yes	Compact instructions for resuming this chunk
`notes`	No	Optional notes about decisions or constraints

Status Transitions

pending ──> in_progress ──> complete
                │
                └──> error (with notes explaining the issue)

Rules:

Set in_progress BEFORE starting work (not after)
Set complete only after tests pass and tracker is verified
Set error if blocked; add notes explaining what went wrong
Never skip in_progress (helps session resumption)

Resume Field Format

The resume field should be a compact instruction block that enables resuming the chunk in a new session without reading the full plan. Structure:

FILES: List files to create/modify
WHAT: One-sentence description of the change
PATTERN: Which existing code to follow (file:function)
DO NOT: Common pitfalls to avoid
TDD: Specific test conditions

Example

FILES: Add searchItems() to ItemRepository interface.
Implement in SqlItemRepository using full-text search.
Extend FakeItemRepository with searchItems().
WHAT: Add search capability to repository layer.
PATTERN: Follow existing getItemsByDate() for query pattern.
DO NOT: Change service return types - wrap result internally.
TDD: Test empty query returns empty, partial match returns filtered, category filtering works.

Batch Chunk Convention

When multiple files must change together (won’t compile between), prefix the tdd field with “BATCH”:

{
  "tdd": "BATCH - all 3 files must change together. No standalone unit test (UI). Verified by build + full suite regression. Update 16 breaking assertions in ServiceTest.",
  "resume": "BATCH - all 3 files must change together (won't compile between). FILES: AppState.ts, AppService.ts, AppView.tsx. ..."
}

Single-Chunk Features

For small features (1 chunk), the tracker is still created but simplified:

{
  "phase": "Feature Name",
  "issue": "org/repo#XX",
  "chunks": [
    {
      "id": 1,
      "name": "Feature description",
      "status": "complete",
      "files_create": [],
      "files_modify": ["path/to/File.ext"],
      "test_files": ["path/to/Test.ext"],
      "acceptance_criteria": ["Describe the pass/fail condition"],
      "tdd": "Pre-test: existing TestClass covers logic. Pure UI change. Post-test: full suite regression.",
      "depends_on": [],
      "notes": "Optional context."
    }
  ],
  "quality_verification": { }
}

Dependency Graph Notation

Document the execution order in the plan (not the tracker):

Layer 1 (no deps):             Chunks 1, 2, 9
Layer 2 (depends on Layer 1):  Chunks 3, 4, 5, 6
Layer 3 (depends on Layer 2):  Chunks 7, 8
Layer N (final):               Chunk 10 (regression + quality)

The final chunk should always be a regression + quality verification chunk that depends on all prior chunks.

This site is open source. Improve this page.