TC Tracker

# TC Tracker Track every code change with structured JSON records, an enforced state machine, and a session handoff format that lets a new AI session resume work cleanly when a previous one expires. ## Overview A Technical Change (TC) is a structured record that captures **what** changed, **why** it changed, **who** changed it, **when** it changed, **how it was tested**, and **where work stands** for the next session. Records live as JSON in `docs/TC/` inside the target project, validated against a strict schema and a state machine. **Use this skill when the user:** - Asks to "track this change" or wants an audit trail for code modifications - Wants to hand off in-progress work to a future AI session - Needs structured release notes that go beyond commit messages - Onboards an existing project and wants retroactive change documentation - Asks for `/tc init`, `/tc create`, `/tc update`, `/tc status`, `/tc resume`, or `/tc close` **Do NOT use this skill when:** - The user only wants a changelog from git history (use `engineering/changelog-generator`) - The user only wants to track tech debt items (use `engineering/tech-debt-tracker`) - The change is trivial (typo, formatting) and won't affect behavior ## Storage Layout Each project stores TCs at `{project_root}/docs/TC/`: ``` docs/TC/ ├── tc_config.json # Project settings ├── tc_registry.json # Master index + statistics ├── records/ │ └── TC-001-04-05-26-user-auth/ │ └── tc_record.json # Source of truth └── evidence/ └── TC-001/ # Log snippets, command output, screenshots ``` ## TC ID Convention - **Parent TC:** `TC-NNN-MM-DD-YY-functionality-slug` (e.g., `TC-001-04-05-26-user-authentication`) - **Sub-TC:** `TC-NNN.A` or `TC-NNN.A.1` (letter = revision, digit = sub-revision) - `NNN` is sequential, `MM-DD-YY` is the creation date, slug is kebab-case. ## State Machine ``` planned -> in_progress -> implemented -> tested -> deployed | | | | | +-> blocked -+ +- in_progress <-------+ | (rework / hotfix) +-> planned ``` > See [references/lifecycle.md](references/lifecycle.md) for the full transition table and recovery flows. ## Workflow Commands The skill ships five Python scripts that perform deterministic, stdlib-only operations on TC records. Each one supports `--help` and `--json`. ### 1. Initialize tracking in a project ```bash python3 scripts/tc_init.py --project "My Project" --root . ``` Creates `docs/TC/`, `docs/TC/records/`, `docs/TC/evidence/`, `tc_config.json`, and `tc_registry.json`. Idempotent — re-running reports "already initialized" with current stats. ### 2. Create a new TC record ```bash python3 scripts/tc_create.py \ --root . \ --name "user-authentication" \ --title "Add JWT-based user authentication" \ --scope feature \ --priority high \ --summary "Adds JWT login + middleware" \ --motivation "Required for protected endpoints" ``` Generates the next sequential TC ID, creates the record directory, writes a fully populated `tc_record.json` (status `planned`, R1 creation revision), and updates the registry. ### 3. Update a TC record ```bash # Status transition (validated against the state machine) python3 scripts/tc_update.py --root . --tc-id TC-001-04-05-26-user-auth \ --set-status in_progress --reason "Starting implementation" # Add a file python3 scripts/tc_update.py --root . --tc-id TC-001-04-05-26-user-auth \ --add-file src/auth.py:created # Append handoff data python3 scripts/tc_update.py --root . --tc-id TC-001-04-05-26-user-auth \ --handoff-progress "JWT middleware wired up" \ --handoff-next "Write integration tests" \ --handoff-next "Update README" ``` Every change appends a sequential `R<n>` revision entry, refreshes `updated`, and re-validates against the schema before writing atomically (`.tmp` then rename). ### 4. View status ```bash # Single TC python3 scripts/tc_status.py --root . --tc-id TC-001-04-05-26-user-auth # All TCs (registry summary) python3 scripts/tc_status.py --root . --all --json ``` ### 5. Validate a record or registry ```bash python3 scripts/tc_validator.py --record docs/TC/records/TC-001-.../tc_record.json python3 scripts/tc_validator.py --registry docs/TC/tc_registry.json ``` Validator enforces the schema, checks state-machine legality, verifies sequential `R<n>` and `T<n>` IDs, and asserts approval consistency (`approved=true` requires `approved_by` and `approved_date`). > See [references/tc-schema.md](references/tc-schema.md) for the full schema. ## Slash-Command Dispatcher The repo ships a `/tc` slash command at `commands/tc.md` that dispatches to these scripts based on subcommand: | Command | Action | |---------|--------| | `/tc init` | Run `tc_init.py` for the current project | | `/tc create <name>` | Prompt for fields, run `tc_create.py` | | `/tc update <tc-id>` | Apply user-described changes via `tc_update.py` | | `/tc status [tc-id]` | Run `tc_status.py` | | `/tc resume <tc-id>` | Display handoff, archive prior session, start a new one | | `/tc close <tc-id>` | Transition to `deployed`, set approval | | `/tc export` | Re-render all derived artifacts | | `/tc dashboard` | Re-render the registry summary | The slash command is the user interface; the Python scripts are the engine. ## Session Handoff Format The handoff block lives at `session_context.handoff` inside each TC and is the single most important field for AI continuity. It contains: - `progress_summary` — what has been done - `next_steps` — ordered list of remaining actions - `blockers` — anything preventing progress - `key_context` — critical decisions, gotchas, patterns the next bot must know - `files_in_progress` — files being edited and their state (`editing`, `needs_review`, `partially_done`, `ready`) - `decisions_made` — architectural decisions with rationale and timestamp > See [references/handoff-format.md](references/handoff-format.md) for the full structure and fill-out rules. ## Validation Rules (Always Enforced) 1. **State machine** — only valid transitions are allowed. 2. **Sequential IDs** — `revision_history` uses `R1, R2, R3...`; `test_cases` uses `T1, T2, T3...`. 3. **Append-only history** — revision entries are never modified or deleted. 4. **Approval consistency** — `approved=true` requires `approved_by` and `approved_date`. 5. **TC ID format** — must match `TC-NNN-MM-DD-YY-slug`. 6. **Sub-TC ID format** — must match `TC-NNN.A` or `TC-NNN.A.N`. 7. **Atomic writes** — JSON is written to `.tmp` then renamed. 8. **Registry stats** — recomputed on every registry write. ## Non-Blocking Bookkeeping Pattern TC tracking must NOT interrupt the main workflow. - **Never stop to update TC records inline.** Keep coding. - At natural milestones, spawn a background subagent to update the record. - Surface questions only when genuinely needed ("This work doesn't match any active TC — create one?"), and ask once per session, not per file. - At session end, write a final handoff block before closing. ## Retroactive Bulk Creation For onboarding an existing project with undocumented history, build a `retro_changelog.json` (one entry per logical change) and feed it to `tc_create.py` in a loop, or extend the script for batch mode. Group commits by feature, not by file. ## Anti-Patterns | Anti-pattern | Why it's bad | Do this instead | |--------------|--------------|-----------------| | Editing `revision_history` to "fix" a typo | History is append-only — tampering destroys the audit trail | Add a new revision that corrects the field | | Skipping the state machine ("just set status to deployed") | Bypasses validation and hides skipped phases | Walk through `in_progress -> implemented -> tested -> deployed` | | Creating one TC per file changed | Fragments related work and explodes the registry | One TC per logical unit (feature, fix, refactor) | | Updating TC inline between every code edit | Slows the main agent, wastes context | Spawn a background subagent at milestones | | Marking `approved=true` without `approved_by` | Validator will reject; misleading audit trail | Always set `approved_by` and `approved_date` together | | Overwriting `tc_record.json` directly with a text editor | Risks corruption mid-write and skips validation | Use `tc_update.py` (atomic write + schema check) | | Putting secrets in `notes` or evidence | Records are committed to the repo | Reference an env var or external secret store | | Reusing TC IDs after deletion | Breaks the sequential guarantee and confuses history | Increment forward only — never recycle | | Letting `next_steps` go stale | Defeats the purpose of handoff | Update on every milestone, even if it's "nothing changed" | ## Cross-References - `engineering/changelog-generator` — Generates Keep-a-Changelog release notes from Conventional Commits. Pair it with TC tracker: TC for the granular per-change audit trail, changelog for user-facing release notes. - `engineering/tech-debt-tracker` — For tracking long-lived debt items rather than discrete code changes. - `engineering/focused-fix` — When a bug fix needs systematic feature-wide repair, run `/focused-fix` first then capture the result as a TC. - `project-management/decision-log` — Architectural decisions made inside a TC's `decisions_made` block can also be promoted to a project-wide decision log. - `engineering-team/code-reviewer` — Pre-merge review fits naturally into the `tested -> deployed` transition; capture the reviewer in `approval.approved_by`. ## References in This Skill - [references/tc-schema.md](references/tc-schema.md) — Full JSON schema for TC records and the registry. - [references/lifecycle.md](references/lifecycle.md) — State machine, valid transitions, and recovery flows. - [references/handoff-format.md](references/handoff-format.md) — Session handoff structure and best practices.