| name | devflow-tdd |
| description | Use during implementation to drive every change through Test-Driven Development. Before writing production code, query existing test-patterns from the LLM-Wiki (Hook 3) for the relevant tag-scope, then write a failing test (RED), make it pass (GREEN), and refactor (REFACTOR). Emits a discipline-token only when each cycle has the prescribed evidence. |
| flow_state | in_progress |
| hooks | [3] |
| discipline_token | devflow-tdd |
| ported_from | superpowers:test-driven-development |
| iron_laws | ["No production code without a failing test first.","REFACTOR happens only after GREEN.","One concern per RED-GREEN-REFACTOR cycle."] |
Skill: devflow-tdd
Iron Law port of Superpowers test-driven-development. The cycle is non-negotiable; this skill refuses to emit a token if any of the three iron laws were broken.
When to use
Use this skill in in_progress state for every code change that introduces or modifies behavior. Pure refactors that change nothing observable are exempt; everything else goes through RED → GREEN → REFACTOR.
Process
0 · Pull existing test-patterns (Hook 3)
Before writing the first test, query the LLM-Wiki for reusable test-pattern doc-pages tagged testing:
GET /api/projects/:projectId/docs?document_type=pattern&tag=testing
(equivalent MCP call: doc_page_list({ projectId, document_type: 'pattern', tags: ['testing'] }))
Cite each pattern that applies via wiki-link in the test file's leading comment, e.g.:
This keeps test conventions consistent across flows and surfaces the patterns in the Knowledge-Graph for future readers.
1 · RED — failing test first
- Write a single test that captures one behavioral expectation.
- Run the test suite. Confirm the new test fails for the expected reason (not a syntax error, not a missing import — the actual assertion).
- Capture the failure output.
2 · GREEN — minimum production code
- Add the smallest amount of production code that makes the new test pass.
- Re-run the suite. Confirm:
- The new test now passes.
- No previously-passing test broke.
3 · REFACTOR — only after GREEN
- Clean up the code (rename, dedupe, extract). Tests stay green throughout.
- Re-run the suite after every non-trivial refactor — never skip the safety check.
4 · Commit & repeat
- One commit per RED → GREEN → REFACTOR cycle (or grouped semantically when the cycles are tightly coupled).
- Then move to the next acceptance-criterion / task. Begin a fresh cycle at step 1.
Iron Laws
No production code without a failing test first.
REFACTOR happens only after GREEN.
One concern per RED-GREEN-REFACTOR cycle.
If you wrote production code first, delete the production code, write the test, watch it fail, then write the production code again. No shortcuts.
Output contract
After completing all cycles for the current task:
POST /api/flows/:id/discipline-tokens
{
"skillName": "devflow-tdd",
"evidence": {
"cycles": [
{ "task": "<acceptance-criterion>", "redOutput": "<truncated stderr>", "greenOutput": "<truncated stdout>", "refactored": true|false }
],
"patternsCited": ["pattern:<slug>", ...],
"completedAt": "<iso>"
}
}
The signed token is returned once. Future review→done check (DF-292) will verify the token is present + non-expired before granting agent_with_discipline self-approval.
What this skill is NOT
- Not a replacement for
devflow-debugging — when an existing test fails unexpectedly, switch to systematic-debugging (4 phases).
- Not a license to write tests of every implementation detail — the test should capture the behavior, not lock in internals.
- Not for documentation-only changes — those go straight to commit.
Related
- [[kn-hook-3-test-patterns]] — design doc
- [[migration-test-strategy]] — Säule A (skill triade) + Säule B (hook integration)
- [[knowledge-gated-workflow]] — Stage 9 in the visual diagram
- DF-291 — port flow (this implementation)
- DF-289 — discipline-tokens foundation
- Superpowers v5.0.7 —
test-driven-development (original skill)
