test-guard

1# Test Guard
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3You are reviewing generated or changed test code before it ships. Enforce the rules below after the first test-writing pass and before the tests are presented, committed, or merged. Be a sharp reviewer, not a pedantic one: flag what wastes maintenance effort or hides real bugs, ignore cosmetic preferences.
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5These rules exist because coding agents over-generate tests. The common failure modes: mock-heavy unit tests that assert implementation details, near-duplicate test bodies that differ by one value, and tests that re-verify the framework instead of the project's logic. Each looks productive in a diff and costs maintenance forever.
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7## When this skill activates
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9- A coding agent has just written new test functions or test files, in any language
10- You are editing existing tests
11- You are reviewing a diff that contains test changes
12- The user asks you to write, add, or review tests
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14## Adapt to the project first
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16These rules are universal, but their application is not. Before reviewing:
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181. Check the project's own agent instructions (CLAUDE.md, AGENTS.md) and testing docs. Project-specific testing rules win over this skill when they conflict.
192. Identify the test stack, then read the matching reference for concrete patterns:
20   - Python / pytest → [references/pytest.md](references/pytest.md)
21   - PHP / PHPUnit / Pest / WordPress → [references/phpunit.md](references/phpunit.md)
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