TestTrout: Instructions file for Codex

Notes for coding agents

Setting this tool up on a project? Follow docs/setup.md top to bottom. Driving it once set up? The skill at .claude/skills/qa-agent/SKILL.md covers the workflow.

The short version

trout scan --json                  # 1. no API key, no network, safe on any repo
                                # 2. write a gitignored .env with credentials
trout init --yes --url <URL> --no-disposable --role owner --role member
trout doctor --json                # verify; exits non-zero and says what is missing
trout probe --role owner --json    # needs: playwright install chromium
trout intent --draft --json        # or --describe "..." / --from FILE
trout plan --json               # what is possible, and what is missing
trout gaps --json               # deterministic; no model, no key
trout propose --json -n 5          # drafts only — never auto-approve
trout scenarios --json
trout approve <id>                 # only when the user has chosen
trout generate --json
trout run --json                   # read `status` before `results`

Or use the MCP server instead of shelling out:

pip install 'testtrout[mcp]' && trout mcp /path/to/project

There is also an app (trout up) over the same state — storage, a worker, and a web interface — if the user prefers a screen. It can hold several repositories at once. The CLI and MCP work identically whether or not it is running.

Rules

1. Always use --json. Every command supports it. Never parse rendered output.
2. trout doctor --json first whenever something fails. It reports exactly what is missing, so guessing is never necessary.
3. Default to --no-disposable. Only mark a deployment disposable when the user confirms its data can be destroyed. Writes against a non-disposable deployment are blocked at the network layer — that guard is the reason this is safe to point at production, so do not disable it to "make the probe work".
4. Never write a secret into .trout/config.yaml. It is committed. Use env:NAME references and put values in .env.
5. Two test users minimum. Authorization tests need a second account to be possible at all.
6. Surface the table_without_rls warning to the user immediately. It means data is world-writable through the browser. It is usually news.
7. Approval belongs to the user. Propose; do not approve on their behalf.
8. Quote criticality_reasons and gap reasons rather than re-deriving your own ranking. They are deterministic and auditable; your restatement is not.
9. Never edit generated test files. They are build artifacts, overwritten on every trout generate. Edit the scenario .yaml and regenerate.
10. A scenario with open questions cannot be approved, and that is correct. Approving it yields a test that passes vacuously. Surface the question to the user instead.
11. On a run, read status first. inconclusive means the run says nothing about the product — do not report it as a pass or a failure. Only assertion_failure is a product signal; auth_failure and environment_failure are about the harness.
12. Never disable database isolation or the substitution boundary to make a run go green. Both exist to stop a test run destroying real data or charging a real card.
13. Report blocked gaps as work, not as failures. needs_two_roles, unreachable, and unresolved_table each name a specific thing the user can fix in under a minute.