principle-fix-root-causes

What the skill teaches

A short principle skill from Cursor's pstack harness for Claude Code, run only when invoked, about fixing a bug where it starts rather than where it shows up. The agent reproduces the problem first, keeps asking why until it reaches a wrong decision in the code, adds instrumentation and reads the real error and state instead of guessing, and decides whether the state that triggered the symptom is legitimate: if so, the code that broke on it gets fixed; if not, it finds what produced that state. It suspects persisted state when failures follow a restart, fixes every instance of the same fault, and proposes a cheap signal that would have shown the cause sooner.

Capabilities

Details