Pulumi has launched OpenAPI support for its Cloud REST API, now defined by an OpenAPI 3.0 specification. This update addresses user requests for a standardized, machine-readable API description. The new specification is essential for enhancing tooling and integration, promising a more consistent experience for developers. Users can retrieve the spec directly from the API with a simple GET request to `https://api.pulumi.com/api/openapi/pulumi-spec.json`, which requires no authentication. The OpenAPI spec allows for various functionalities: API client generation in multiple programming languages using tools like OpenAPI Generator or Swagger Codegen, validation of requests and responses for testing, and interactive documentation through platforms like Swagger UI. Pulumi generates this spec automatically from the same backend definition that powers its services, ensuring that the documentation remains accurate and up-to-date with any changes to the API. Future plans include integrating this spec into the Pulumi CLI for better synchronization and enhancing public REST API documentation to reflect the OpenAPI standard. Users are encouraged to provide feedback via Community Slack or the Pulumi repository.