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Idempotency & Reliability

Headers that make a retry safe. Almost entirely a payments-industry invention that the rest of the API economy has not adopted.

7 headers, ordered by how many providers in the catalog declare them.

Idempotency-Key 127 providers 4 spellings

The header that makes a retry safe. A payments-industry invention the rest of the API economy has barely adopted.

x-idempotency-key 45 providers regulated 2 spellings

The x-idempotency-key HTTP header — idempotency & reliability, declared by 45 providers in the API Evangelist catalog.

Repeatability-Result 1 providers

The Repeatability-Result HTTP header — idempotency & reliability, declared by 1 providers in the API Evangelist catalog.

Repeatability-Request-ID 1 providers 2 spellings

The Repeatability-Request-ID HTTP header — idempotency & reliability, declared by 1 providers in the API Evangelist catalog.

Repeatability-First-Sent 1 providers 2 spellings

The Repeatability-First-Sent HTTP header — idempotency & reliability, declared by 1 providers in the API Evangelist catalog.

Safe

The Safe HTTP header — idempotency & reliability, RFC 2310, not observed in the catalog.

Repeatability-Client-ID

The Repeatability-Client-ID HTTP header — idempotency & reliability, not observed in the catalog.