typescript-async

name	typescript-async
description	Use when TypeScript code coordinates async work — Promise.all vs sequential, bounded concurrency, AbortSignal cancellation, cleanup/teardown, or process lifecycle (SIGTERM, graceful shutdown).

TypeScript Async

Use this skill when async coordination is the question: should this be parallel? Can it be cancelled? What cleans up if it fails halfway? What happens at SIGTERM?

Agent Quick Path

If you see...	Read
sequential awaits for independent operations, or Promise.all question	rules/parallel-and-dependencies.md
500 IDs in Promise.all causing rate-limit, batching, p-limit, p-map	rules/parallel-and-dependencies.md
fetch without AbortSignal, query that should cancel on unmount, hanging request	rules/cancellation-and-abort.md
resource left open on error, missing finally, using/Disposable question	rules/cleanup-and-teardown.md
SIGTERM, graceful shutdown, unhandledRejection, process.on, draining requests	rules/process-lifecycle.md
retry loop, exponential backoff, jitter, Retry-After, idempotency key	rules/retry-and-backoff.md

Owns

• Concurrency policy (parallel vs sequential vs bounded).
• Cancellation propagation via AbortSignal / AbortController.
• Operation-level cleanup (finally, using, dispose).
• Process-level lifecycle (signal handlers, graceful shutdown, unhandled rejection, top-level error handlers).
• Retry mechanism: backoff, jitter, attempt cap, AbortSignal-aware, library-or-hand-rolled.
• Idempotency considerations for retried operations (idempotency keys, safe-to-retry semantics).

Does Not Own

• Dependency lifecycle and scope (use ../typescript-composition/rules/dependency-scope.md).
• Whether failure becomes throw or Result (use ../typescript-error-handling/).
• Tracing async context propagation (use ../typescript-observability/rules/tracing-boundary.md).
• Retry classification (use ../typescript-error-handling/rules/error-classification.md); this skill owns the retry mechanism, not the retry decision.

Default

Sequential await is correct when one operation needs the previous result. Promise.all for independent operations. Bound concurrency when the input set can grow unbounded. Pass AbortSignal as a capability when an operation may be cancelled. Clean up resources in finally or with using. Handle SIGTERM at the process boundary so requests drain instead of being killed mid-flight.