FactCheck Guard — Runtime Claim Verification

Prevents false claims about the codebase. Grep results are hypotheses, not proof. Every assertion about "what the code does" must be verified by reading the actual code.

Why This Exists

An 80% false claim rate was observed when agents trusted grep results without reading files. The pattern repeats: grep finds a string, agent asserts behavior, behavior is wrong. This skill converts the claim-verification guidelines into an actionable protocol.

Confidence Markers (MANDATORY)

Every factual claim about the codebase MUST carry one of these markers: