Catch flaws in your plan before you build.
Challenges change specifications against evidence and returns a go/no-go verdict with proposed safeguards.
When to use it
Use before high-impact changes, when dependent interfaces or safeguards change, or when reviewing costs less than a wrong build; skip trivial, reversible changes.
Give it a specification in the project; it returns evidence-backed findings, draft safeguards, and an explicit go/no-go verdict.
What you provide
Hands draft safeguards to spec to write into the specification; whether that skill must already be installed is unstated.
This skill
best-practice documentation
Fetches current best-practice guidance