# Testing Anti Patterns

> Use when reviewing tests for fragility, over-mocking, false positives, missing production wiring, or assertions that do not prove the requirement.

- Skill: `dyai2025/testing-anti-patterns` (Agent Skill)
- Install (CLI): `npx skillmds@latest add dyai2025/testing-anti-patterns`
- Raw SKILL.md: https://api.skillmd.com/api/skills/dyai2025/testing-anti-patterns/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: DYAI2025 (https://skillmd.com/u/dyai2025)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/dyai2025/testing-anti-patterns

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# Testing Anti-patterns

Watch for:
- Tests that assert implementation details instead of behavior.
- Mocks that replace the behavior being tested.
- No negative, boundary, or failure-path coverage.
- Snapshot-only assertions.
- Tests that pass without production wiring.
- Flaky timing or network dependencies without isolation.

For each issue, propose the smallest test change that would fail on the current bug.