SKILL-038 APIs, integrations, and automation Locked skill

Idempotency keys

The unique constraint on the key is the lock; store the response so a replay returns the same answer instead of doing the work twice.

01

What this skill helps you build

Let clients safely retry unsafe writes — a client-supplied key makes a payment, job, or record creation happen at most once.

The production takeaway

The unique constraint on the key is the lock; store the response so a replay returns the same answer instead of doing the work twice.

02

Inside this skill

The full skill expands these implementation areas with decisions, edge cases, prompts, tests, and framework-specific code.

APIs, integrations, and automation
What this helps you build

A way for clients to safely retry an unsafe write — a charge, an outbound job, a record creation — without doing it twice. The client sends a unique Idempotency Key with the reques

🔒
APIs, integrations, and automation
When to use this

Use this any time a request is not naturally safe to repeat and the client might repeat it — because mobile networks drop, load balancers time out, and users mash buttons. Concrete

🔒
APIs, integrations, and automation
The core idea

A client supplies a key that makes a write happen at most once . You store a mapping of key result . The first request with a given key does the real work and saves its response un

🔒
03

Unlock the full implementation

Paid access includes the complete skill body, implementation prompt, common mistakes, production checklist, and code examples where this skill includes them.