# What is an idempotency in Provely?

> The property that a retried request creates no second side effect. The Provely definition, with an example.

Canonical: https://provely.sh/glossary/idempotency  
Last reviewed: 2026-09-05  

**Idempotency means that a retried request creates no second side effect. Provely binds an idempotency key to each operation in `begin`. The agent sends that key with the provider request.**

Stripe reads the `Idempotency-Key` header. Resend reads the same header. Shopify states no key for `refundCreate` in the sources the compiler read, so that skill records an uncertainty instead of a guess.

## Read next

- [Read the definition of Correlation](https://provely.sh/glossary/correlation)
- [Read the definition of CONTRADICTED](https://provely.sh/glossary/contradicted)
- [See every glossary term](https://provely.sh/glossary)
- [Read how Provely works](https://provely.sh/how-it-works)