Test Challenger

A test is only as valuable as its independence from the code it tests. When expected behavior is derived by observing code rather than understanding the spec, the test cannot catch bugs — only regressions. This skill identifies tests likely validating what the code does rather than what the code should do.

The Oracle Problem

Every meaningful test has:

1. Stimulus — calling the code with inputs
2. Oracle — expected result, from an independent source of truth

Human-written: oracle from spec, domain knowledge, requirements. AI-generated by observing code: oracle from the code itself. Circular: the test validates the code, but the code defined the test. Tautology — never fails for the right reasons.

This skill applies challenge patterns to estimate the probability that a test's oracle was derived from the code rather than from genuine domain understanding.

How to Execute