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Header category

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
175 provider declarations
HeaderProvidersStatus
Idempotency-Key 127 de-facto
x-idempotency-key 45 de-facto regulated
Repeatability-Result 1 provisional
Repeatability-Request-ID 1 provisional
Repeatability-First-Sent 1 provisional
Safe obsoleted
Repeatability-Client-ID provisional

All categories

Authentication Authorization & Scope Caching Conditional Requests & Concurrency Content Negotiation Representation Metadata Connection & Transport CORS Security Policy Privacy & Consent Rate Limiting & Quota Tracing & Correlation Idempotency & Reliability Versioning & Lifecycle Integrity & Signing Async & Long-Running Cost & Metering Agent & Bot Identity