What Could Break

Overview

Listing callers is not the job. Grep does that in a second. This skill finds the breakage grep will not show you, and tests the specific assumptions supporting the change.

Run it before design, not only before merge. Whenever a task asserts something about existing code ("X already handles Y", "just make X public"), that assertion is a hypothesis, and the census of real consumers decides the design.

When to Use

• Use before any multi-file edit, or an edit to a shared path: API payload, config, stored data, a client other apps read, a prompt or policy file
• Use when the user asks "what could this break" or "blast radius of X"
• Use for a small diff you do not trust
• Use when a brief asserts something about existing code, before you design against that assertion

How It Works