Individual skill
principle-test-behavior-not-implementation
Call the system the way its consumer does and assert meaningful observable output; avoid mocks or assertions that only mirror internal calls. Use when when writing or evaluating tests.
skills/principle-test-behavior-not-implementation/SKILL.md
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SKILL.mdcore · 815 bytes
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# Test Behavior, Not Implementation
## Trigger
When writing or evaluating tests.
## Rule
Call the system the way its consumer does and assert meaningful observable output; avoid mocks or assertions that only mirror internal calls.
## Application
1. Name the concrete decision this principle changes.
2. Apply the rule to that decision, not as a decorative citation.
3. Prefer evidence from the current repository/runtime over generic preference.