Verification as a Gate

In Factory, an agent’s own report is commentary; the exit code is the evidence.

Why Independent Verification?

A completion message cannot prove that the declared checks ran in the intended worktree. The worker therefore repeats verification outside the agent process.

Factory workers enforce an independent verification gate:

1. The agent finishes writing code and calls its completion tool.
2. The orchestrator worker executes the ticket’s exact Verification Command in the worktree.
3. If the command exits non-zero:
   • The run does not advance to a successful handoff.
   • Failure output and receipt data are retained.
   • Recovery policy decides whether the ticket is retried, returned to the queue, or held for a human.

Writing Verification Commands

A robust verification command should verify both functionality and style:

bun test event-runtime/lib/dispatch.test.mjs && bun run format:check && bun run lint

Negative Testing & Falsifiability

When authoring a regression test, observe it fail against the pre-fix implementation and pass after the fix. A test that already passes does not demonstrate the reported failure mode.