Analyze Test Failures

Read and follow Test Failure Mindset, including its Python standards route. It owns the investigation protocol; this skill applies it to each supplied failure. Reuse an existing evidence record instead of restarting completed investigation.

Per-failure application

Read the complete relevant test, fixtures, setup/cleanup, stack trace, and product path. Preserve the failed revision and conditions; reproduce safely when permitted. Trace the product and test observation to their earliest demonstrated contract divergence.

For each candidate explanation, identify a discriminating observation and separate observed facts from unverified inference. Verify which requirement governs the expected behavior. A familiar mathematical, library, or API convention alone does not establish this product's contract.

Classify supported defects separately as product implementation, interface/architecture, test oracle, or harness/CI; several may coexist. For missing authority, report the intent decision. For missing execution, report unvalidated behavior rather than silently choosing a side.