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 ## Design / Architecture / Development
 | Name | Description |
 | ---- | ----------- |
+| [The API Specification Toolbox](http://api.specificationtoolbox.com) | This Toolbox goal is to try and map out all of the different API specifications in use, as well as the services, tooling, extensions, and other supporting elements. |
 | [Understanding gRPC, OpenAPI and REST](https://cloud.google.com/blog/products/api-management/understanding-grpc-openapi-and-rest-and-when-to-use-them) | gRPC vs REST: Understanding gRPC, OpenAPI and REST and when to use them in API design |
 | [REST API Design Guide](https://www.apiopscycles.com/resources/rest-api-design-guide) | This design guide or style guide contains best practices suitable for most REST APIs. |
 | [How to design a REST API](https://blog.octo.com/en/design-a-rest-api) | How to design a REST API? - Full guide tackling security, pagination, filtering, versioning, partial answers, CORS, etc.