Tyk Classic API definition
An API definition written in Tyk’s proprietary API Specification format. This fully describes how Tyk should be configured to resolve calls made to the API.
Tyk OAS API definition
An API definition that combines an OpenAPI Document with the Tyk vendor fields (
x-tyk-api-gateway) that provide the instructions on how Tyk should be configured to resolve calls made to the API that is described in the OAS part.
An instance of the OpenAPI Specification that describes a service. This is vendor (i.e. API Gateway) agnostic and so, on its own, is not sufficient to configure an API Gateway such as Tyk. Typically you would ‘import’ this into Tyk to convert it into a Tyk OAS API definition by addition of the Tyk vendor fields. You could also add the appropriate fields manually in your editor of choice. There is an option to export a Tyk OAS API Definition from Tyk as an OpenAPI Document. This provides all the information a developer needs to use the API, without the Tyk configuration fields they don’t need to know about.
OpenAPI Specification (OAS)
The OpenAPI Specification, previously known as the Swagger Specification, is an open standard specification that describes a language-agnostic interface to HTTP APIs which allows both humans and computers to discover and understand the capabilities of the service without access to source code, documentation, or through network traffic inspection.