3AceShowHand

Use for deep code review, self-review of the current local branch or worktree, review of a remote pull request or branch, design review…

Use for behavior-preserving refactors, staged rewrites, module moves, symbol renames, dependency inversion, interface simplification…

Make user-facing narrative text clear, precise, concise, and useful.

Use when understanding an unfamiliar codebase, tracing architecture, data flow, or control flow, locating definitions, callers, or…

Use when a change may affect whether existing users can upgrade an application without failures during rollout or after upgrade.

Use when diagnosing or fixing functional bugs, flaky tests, regressions, crashes, data corruption symptoms, production incidents, or…

Use when a change affects distributed coordination, replication, partitioning, ownership transfer, ordering, idempotency, progress…

Use when implementing a non-trivial feature or enhancement that requires coordinated design, code changes, and verification across…

Use when a change affects persisted data, schemas, storage formats, metadata, checkpoints, indexes, config formats, irreversible…

Use when the task is to design or assess production diagnosability and operator readiness through logs, metrics, traces, alerts…

Use for performance optimization, performance regression analysis, throughput, latency, memory, CPU, allocation, IO, concurrency…

Use when creating, updating, auditing, or standardizing a repository-level AGENTS.md.