regression-risk-mapperlisted

Maps what a change can reach — a change being considered as readily as one already made, since the question is usually asked before the edit exists. Finds the symbols involved, traces every call site and importer across the repository, and marks which of those call sites are exercised by a test and which are not. Use when the user asks what something might break, what depends on a symbol they are about to modify, rename or change the return type of, how far the blast radius of a refactor extends, or whether an edit is safe to make. Not for finding usages as an end in itself — with no change in prospect, that is a plain search and answering it with a risk analysis is more than was asked.
Contexory/skills · ★ 0 · AI & Automation · score 73

Install: claude install-skill Contexory/skills

# Regression risk mapper The diff shows what you changed. It does not show who was relying on it. This skill answers the second question, and it answers it with call sites rather than with intuition. The failure it prevents is specific and common: a signature or behaviour is changed with its two obvious callers updated, and the third caller — in another package, reached through a re-export, written before anyone currently on the team joined — is discovered in production. ## Procedure ### 1. Map the radius `<skill-dir>` is the directory this SKILL.md was loaded from — the skill installs outside your project, so its script is named by full path, never relatively. ``` python3 <skill-dir>/scripts/blast_radius.py # working tree vs merge-base with main python3 <skill-dir>/scripts/blast_radius.py origin/main # or an explicit base ``` For every symbol the diff modifies, the script finds every file referencing it, marks each reference `direct` or `re-export`, and marks whether the referencing file has a corresponding test file. It prints a per-symbol radius, ordered by number of call sites. **Read the caveat it prints.** The search is textual. It cannot see dynamic dispatch, string-keyed lookup, reflection, or a caller in another repository, and it says so — those are the paths that stay invisible and they are exactly where the expensive surprises live. ### 2. Separate signature changes from behaviour changes They fail differently and need different checks: - **