Skill Claude CodeCodex
Resolve uncertain product or architecture decisions before implementation. Use for explicit brainstorming or design requests, or when unresolved trade-offs, blast radius, or reversal cost could materially change the implementation; clear, local, reversible work proceeds directly.
Skill Claude CodeCodex
Evidence-backed review of source code and machine-consumed implementation artifacts, including tests, configuration, schemas, migrations, build scripts, and Git workspaces, diffs, commits, PRs, or ranges. Use only when the target is code or implementation behavior and the user explicitly asks to find defects or risks…
Skill Claude CodeCodex
Apply lightweight safeguards when task execution involves completion claims, destructive or external-state changes, debugging, long-running or resumable work, subagent delegation, or high-risk review. Use to preserve evidence, recoverability, and user control without imposing a fixed development workflow.
Skill Claude CodeCodex
Resolve code placement and repository-map trust from repository evidence. Use automatically for existing-repository behavior changes with unclear ownership, cross-boundary impact, entry-point or dependency changes, unfamiliar non-local scope, or missing or stale maps. Also use for dependent-skill repository-context…
Skill Claude CodeCodex
Review a Markdown design document, consume an accepted fix queue, or independently verify accepted fixes with layered contract extraction, architecture reasoning, adversarial falsification, deterministic evidence gates, risk-based partial re-review, and human-only admission. Use only when the user explicitly invokes…
Skill Claude CodeCodex
Find and, when mutation is explicitly authorized and repository-aware evidence supports it, remove redundant production surface such as dead or superseded code, duplicated state, unused APIs, speculative abstractions, obsolete compatibility paths, dependencies, packages, tests, and documentation. Use for explicit…
Skill Claude CodeCodex
Execute test-driven development through coherent red-green-refactor slices. Use when the user explicitly asks for TDD, test-first, red-green-refactor, or a regression test before fixing a bug. Always pair it with testing-guidelines when adding or changing tests; ordinary test requests use testing-guidelines without…
Skill Claude CodeCodex
Design, add, modify, or review automated tests and test strategies using risk-driven evidence selection. Use for unit, integration, regression, and end-to-end test work, including as the test-design companion to TDD. Do not use merely to run existing tests or report their results; this skill does not impose test-first…
Skill Claude CodeCodex
Route substantive tasks to the smallest set of explicitly requested or strongly matching skills. Use at task start when skill selection can materially change the process.