Explains every line of a .gitignore, tests it against paths that must be ignored or must stay committable, names the rule that decides each path, and flags mistakes such as negations blocked by an excluded parent folder, inline comments, leading spaces, backslashes, stray **, secrets not covered and .env.example ignored. Returns a fixed file. Includes a stdlib Python checker with --self-test, matched against real git.
Compares an OpenAPI YAML/JSON spec to a list of implemented routes and flags drift: missing operations, extra routes, method mismatches, and path-parameter shape differences. Use when reviewing API PRs, before a release, or asking "does our code still match the OpenAPI?". Includes a stdlib Python checker with --self-test.
Catches quality drops when you change an AI feature's prompt or model: runs your test cases, compares old and new answers side by side, and tracks cost and speed.
Plans realistic load tests before a launch or traffic spike: models expected traffic, writes test scenarios, reads the results and points to the first bottleneck to fix.
Plans a major framework upgrade step by step, such as React, Next.js, Django or Rails: reads the breaking changes, maps what in your code they hit, and splits the work into small safe pull requests.
Runs the code examples in your README and docs against the latest release, finds snippets that no longer compile or return the wrong output, and drafts the fixed examples for review.
