Design your APIs with Postman Collections

Types in collections enables you to add more details to request parameters, headers, and bodies in an HTTP collection. Define properties such as type, format, and possible values. You can also specify if a component is required. Before you send a request, Postman checks it using the defined properties and identifies possible issues. All the details appear in the collection's documentation for both API developers and consumers.

When you're ready to verify the quality of your APIs and deploy to an API gateway, generate an API specification from your collection and keep them in sync.

Define properties in your requests

After you turn on types in a collection, you can define properties in your requests that describe your API. This enables you to design and test your APIs using the Postman Collection format you're familiar with. Properties can help your team and API consumers understand your API and send valid requests. Learn how to add properties to parameters and headers.

You can also add body data to a request or saved example and generate a schema from the body data. The schema includes properties based on the body data. Optionally, you can add descriptions or specify required properties. Learn how to add properties to body data.

View properties and documentation

Your team and API consumers with access to a collection with types turned on can view properties in the collection and its documentation. Postman notifies you if the request parameter, header, or property in the body data is required to send the request. You can also hover over a parameter, header, or property in the body data to learn more.

Before you send a request, Postman checks the value against the defined properties and notifies you if the value isn't valid. Also, anyone with access to the collection can view details associated with your parameters, headers, and bodies in your collection's documentation.

Learn how to view properties and documentation in a collection.

Generate a specification from a collection

Once you've designed and tested your APIs in a collection, automatically generate an OpenAPI 3.0 specification in Spec Hub. You can use the specification to check your APIs' quality and deploy to an API gateway. Generated specifications have paths, components, and more based on your collection. Postman recommends that you turn on types in the collection to generate a complete OpenAPI 3.0 specification.

When you make changes to the collection, update the generated specification with your latest changes. This ensures team members relying on the specification can access the latest iteration of your APIs.

Learn how to generate a specification from a collection and keep them in sync.