Operations
Idempotency key
An idempotency key is a unique identifier (typically UUID) you supply with API requests so the downstream system recognises duplicates and safely de-duplicates. Stripe, GitHub, Slack, AWS all accept idempotency keys.
More detail
Why it matters: webhooks fire 1-3 times per event. Without idempotency, you create 3 customers / send 3 emails / charge 3 cards. With idempotency key per logical event: downstream API recognises the duplicate and returns the original response without re-executing. Aiprosol's Workflow Automation Playbook covers idempotency as one of 14 patterns.