openapi: 3.1.0 info: title: WunderGraph Cosmo Platform Analytics Feature Subgraphs API description: The WunderGraph Cosmo Platform API provides programmatic access to manage federated GraphQL architectures at scale. It powers the Cosmo CLI (wgc) and Cosmo Studio, enabling management of federated graphs, subgraphs, namespaces, schema contracts, feature flags, router configurations, and API keys. The API uses Connect-RPC protocol with HTTP/JSON support. Cosmo is the open-source alternative to Apollo GraphOS for full lifecycle GraphQL federation management including schema registry, composition checks, analytics, metrics, tracing, and routing. version: 1.0.0 contact: name: WunderGraph url: https://wundergraph.com license: name: Apache 2.0 url: https://www.apache.org/licenses/LICENSE-2.0 servers: - url: https://cosmo-cp.wundergraph.com description: WunderGraph Cosmo Cloud Control Plane tags: - name: Feature Subgraphs description: Manage feature subgraphs for experimental feature development. paths: /v1/feature-subgraphs: post: operationId: createFeatureSubgraph summary: WunderGraph Create a feature subgraph description: Creates a feature subgraph based on an existing subgraph for gradual and experimental feature rollout using feature flags. tags: - Feature Subgraphs security: - apiKey: [] requestBody: required: true content: application/json: schema: type: object required: - name - baseSubgraphName properties: name: type: string description: The name of the feature subgraph. namespace: type: string description: The namespace for the feature subgraph. baseSubgraphName: type: string description: The name of the base subgraph this feature is based on. routingUrl: type: string format: uri description: The routing URL for the feature subgraph. responses: '200': description: Feature subgraph created successfully content: application/json: schema: $ref: '#/components/schemas/OperationResponse' components: schemas: OperationResponse: type: object properties: success: type: boolean description: Whether the operation was successful. message: type: string description: A human-readable response message. securitySchemes: apiKey: type: apiKey in: header name: Authorization description: API key for authenticating with the Cosmo Platform API. Obtain via Cosmo Studio or wgc CLI. Set as COSMO_API_KEY environment variable.