> **Preview:** This loop runs across our internal repositories today. Its driver source lives in `starlight-agent-config` and is documented here before public standalone release. If you want it packaged first, open a request on [GitHub issues](https://github.com/frankxai/Starlight-Intelligence-System/issues).

Ask a coding agent to write tests for a module, run them, and fix failures, and it will try. What it will not do reliably on its own is stop after a bounded number of attempts, preserve an audit trail, or catch itself when it quietly weakens a test assertion to turn a red run green. The build-fix loop enforces those three invariants across every harness.

## The six-step loop [#the-six-step-loop]

1. **Take a baseline.** Run the suite before touching code. Pre-existing failures belong to the baseline, not to your diff.
2. **Reproduce first.** For any bug fix, write the smallest test that fails for the reported reason and observe the failure before editing implementation code.
3. **Fix the code, not the test.** Modify a test only when the test itself is defective, and record the reason in the commit message.
4. **Stop on the attempt budget.** Five attempts by default, locked when the loop starts. If two consecutive runs fail with the same error signature, change approach instead of retrying.
5. **Widen to the full suite.** Once scoped tests pass, run the full test suite, typecheck, and linter. A scoped pass is not completion.
6. **Cross-provider verification.** A model from a different provider reviews the exact diff before the PR is marked ready.

## What the driver verifies automatically [#what-the-driver-verifies-automatically]

- **Multi-language runner detection:** Discovers `pnpm`, `npm`, `yarn`, and `bun` scripts, `node --test`, `pytest` (via `uv` when present), `unittest`, `cargo test`, `go test`, and PowerShell `Pester`.
- **Real execution proof:** A zero exit code counts only when runner output proves at least one test executed. Skipped or todo-only runs are flagged as `no-tests`.
- **Weakened-test guard:** Snapshots test files and runner configurations (`package.json`, `pytest.ini`, `tsconfig.json`) before iteration 1, flagging deleted assertions, newly skipped tests, or narrowed test globs.
- **Monotonic budget:** Attempt counters decrement before each run begins so crashed runs count against the ceiling.