Use when investigating root cause with the Five Whys method: gather evidence across the full problem space, ask five explicit why questions in sequence, and answer each why with a Because line that connects each cause to the prior answer.
Use when adding or repairing GitHub Actions release automation that builds multi-arch container images on semver tags, pushes them to GitHub Container Registry, updates example healthcheck manifests, creates GitHub releases, and documents the tag-only release process in RELEASE.md.
Use for complex, multi-factor incidents. Recursively split causes into binary branches, pursue one path to a single concrete fix, then backtrack through sibling branches and implement fixes one at a time until the issue-level check passes.
Use when you need to convert session history into reusable, repo-specific workflow skills from repeated service-specific discovery.
Use when adding, updating, or consulting repository-local `ADR.md` architecture decisions. Keep ADR authority user-owned and ensure planning flows load `./ADR.md` via `AGENTS.md`.
Use only at workspace root in a multi-service repo with authoritative `ARCHITECTURE.md` when deciding cross-repo ownership, compatibility, or service-to-service contracts. Do not use for service-local `SPEC.md` work.
Use when deciding whether a behavior change belongs in centralized policy, a shared abstraction, or a local call site. Prefer narrow high-leverage shared fixes for cross-cutting behavior.
Use when standing up a full local multi-service test stack for cross-service validation, with shared dependencies, deterministic namespaces, and controlled test lifecycle.