OpenAPI Editor & Contract Tester
Web & network Local only
AsyncAPI Editor & Validator
Local contract · optional refsValidate, explore, sample, migrate, and compare AsyncAPI event-driven contracts.
Paste an AsyncAPI 2.x or 3.x YAML/JSON document…
Contract parsing, migration, samples, validation, and diff run locally.
Ready for an event contract
Paste or open AsyncAPI YAML/JSON, then analyze servers, channels, operations, messages, payload schemas, bindings, and evolution risk.
How to use it
- 01
Load the event contract
Paste or open AsyncAPI YAML or JSON, then inspect structural diagnostics without uploading it.
- 02
Explore and test messages
Browse servers, channels, send/receive operations, messages and bindings, then generate and validate example payloads.
- 03
Evolve the contract
Preview explicit HTTPS references, migrate a 2.x document to a 3.0-oriented structure, or compare contracts for risky removals and routing changes.
Frequently asked questions
Does this tool connect to MQTT, Kafka, AMQP, or another broker?
No. AsyncAPI describes event contracts across protocols; use the explorer for contract work and a protocol-specific client for live broker traffic.
How are AsyncAPI 2.x publish and subscribe shown?
They are normalized from the application's perspective: publish becomes send and subscribe becomes receive, matching AsyncAPI 3.0 action terminology.
Are remote references fetched automatically?
No. External HTTPS references are listed and fetched only when you click preview. Browser CORS and the target server still decide whether the response is readable.
Is every reported change definitely breaking?
No. The comparison flags structural risks such as removed channels or changed operations. Consumer behavior, broker rules, bindings, and deployment policy still need review.
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