# Tests that can't fail

Prompt · Testing and security · T02

Finds tests that pass no matter what.

## Prompt

```text
Find tests that would continue passing if the underlying feature stopped working. Examine mocks, fixtures, assertions, and tests that merely reproduce implementation details.
```

**What it returns:** For each suspect test, break the feature on purpose and show the test still passes.

**Skip it when:** Brand-new test suites written before the code.

**Tools:** Repository and the test runner.

**Changes:** Adds a test that shows it

**Sessions:** One session

## Skills

- [tdd](https://atlasscope.dev/skills/tdd): Test-driven development.

## Related

- [What the tests really prove](https://atlasscope.dev/prompts/what-the-tests-really-prove): Asks what each test really proves, then adds one check that would catch a real break.
- [Unit tests that give false comfort](https://atlasscope.dev/prompts/unit-tests-that-give-false-comfort): Finds features whose automated checks all pass and that still break for real people.

Source: https://atlasscope.dev/prompts/tests-that-cant-fail