Feature
Idempotency
Safe retries without duplicate side effects.
22 providers
240 APIs
15 declared variants
Idempotency keys or exactly-once semantics let clients retry after a timeout without double-charging or double-writing. Essential wherever operations move money or state.
22 API providers on the APIs.io network offer idempotency. The highest-rated are Messagebird, Stripe, Novu, Knock, Deel.
Providers
Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.
Exemplar 5 Complete, well-documented, and agent-ready
MessagebirdMessageBird, which trades as Bird, is a Dutch cloud communications company whose platform carries email, SM...StripeOnline payment processing for internet businesses. Stripe is a suite of payment APIs that powers commerce f...NovuNovu is the open-source notification infrastructure for developers. A single REST API and workflow engine r...KnockKnock is notifications infrastructure as a service — a product and customer messaging platform you use to p...DeelDeel is a global workforce platform combining payroll, Employer of Record (EOR), independent contractor man...
Strong 6 Solid coverage with minor gaps
Amazon NeptuneAmazon Neptune is a fast, reliable, fully managed graph database service that makes it easy to build and ru...FlutterwaveFlutterwave is a pan-African payment infrastructure company providing the rails for businesses to accept, s...RaygunRaygun is an application monitoring platform that combines Crash Reporting, Real User Monitoring (RUM), and...WalmartWalmart is a multinational retail corporation that operates a chain of hypermarkets, discount department st...CouchbaseCouchbase is a distributed, document-oriented NoSQL cloud database platform that combines the flexibility o...CivitaiCivitai is the largest open community for Stable Diffusion, SDXL, Flux, and video AI models — hosting over ...
Developing 5 Usable, with meaningful gaps to close
JustworksJustworks is a New York City-based Professional Employer Organization (PEO) and small-business HR platform....Apache KafkaApache Kafka is an open-source distributed event streaming platform used by thousands of companies for high...Apache IcebergApache Iceberg is an open table format for large analytic datasets that provides ACID transactions, schema ...CockroachDBCockroachDB is a distributed SQL database with strong consistency, PostgreSQL compatibility, and a managed ...Apache IgniteApache Ignite is a distributed database for mission-critical high-velocity applications requiring in-memory...
Thin 5 Limited public surface area
Apache GeodeApache Geode is an in-memory data management platform that provides real-time, consistent access to data-in...Apache HiveApache Hive is a data warehouse software that facilitates reading, writing, and managing large datasets res...Apache FlinkApache Flink is a framework and distributed processing engine for stateful computations over unbounded and ...Apache DerbyApache Derby is an open-source relational database implemented entirely in Java, formerly governed by the A...Apache RocketMQApache RocketMQ is a distributed messaging and streaming platform with low latency, high performance, and r...
Emerging 1 Early or largely undocumented
What Providers Actually Declared
This feature is a canonical term. These are the free-text strings
providers wrote in their own apis.yml that map onto it.
ACID TransactionsACID transactions across regionsCrash Reporting — error detection, deduplication into error groups, full stack-trace and breadcrumb contextDeductions endpoints (list types, list, create, update, cancel) with per-row operation_id idempotencyExactly-Once SemanticsHTTPS-only webhook endpoints with retry on non-2xx; idempotency keyed on `(workflowId, status, timestamp)`Idempotency + RateLimit HeadersIdempotency keys on POST/PATCH via UUID v4 with 24-hour response cacheIdempotency via `X-Idempotency-Key` (UUID) returned on retry with `X-Idempotency-Cache-HitIdempotency-Key header support for safe automatic retriesIdempotency-Key support for safe retriesIdempotent requests via Idempotency-KeyMulti-document ACID transactionsNo idempotency mechanism anywhere in the surface — writes are not replay-safeOpt-in Idempotency-Key on POST/PATCH/PUT/DELETE, 3-hour replay window
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