Validate an API specification

As you edit your specification, Postman identifies syntax errors, such as wrong data types and nesting, and shows details about the errors so you can correct them. Postman also identifies API governance issues in OpenAPI 3.0 specifications based on the rules configured for your team.

View syntax errors in your specification

Postman automatically identifies syntax errors as you edit your API specification. Errors can include missing fields, malformed field names, wrong data types, wrong nesting, or other issues. For Postman to be able to check your specification elements, you must use valid JSON or YAML.

To view any syntax errors, select Syntax below the specification editor. Each syntax error shows the number of times Postman found it in the specification, details about the error, and the severity.

Select the number next to each syntax error to view more details. Every instance of the syntax error has a brief description and the line where the error occurs. Select an instance of the syntax error to navigate to it in the specification. You can also get details about the syntax error by hovering over it in the specification.

View rule violations in your specification

API governance rule validation is available with Postman Enterprise plans.

As you edit your OpenAPI 3.0 specification, Postman automatically checks it against the Postman API Governance rules configured for your team.

To view any rule violations, select Governance below the specification editor. Each rule violation shows the number of times Postman found it in the specification, details about the rule violation, and the severity.

Select the number next to each rule violation to view more details. Every instance of the rule violation has a brief description and the line where the violation occurs. Select an instance of the rule violation to navigate to it in the specification. You can also get details about the rule violation by hovering over it in the specification.