WunderGraph Feature Subgraphs API

openapi: 3.2.0
info:
  title: WunderGraph Cosmo Platform Feature Subgraphs API
  description: The WunderGraph Cosmo Platform API provides programmatic access to manage federated GraphQL architectures at scale.
  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.
x-authored-by: API Evangelist
x-modeled-from: documentation
x-provenance:
  method: modeled
  authored_by: API Evangelist
  modeled_from: https://cosmo-docs.wundergraph.com/
  provider_published: false
  note: Modeled by API Evangelist from WunderGraph's public Cosmo documentation. The provider does not publish a REST OpenAPI. The real control-plane interface is Connect-RPC, defined in WunderGraph's own platform.proto — see grpc/ for the verbatim first-party contract, which is authoritative where this document and the proto disagree.
  verified: '2026-08-03'
  evidence:
  - url: https://cosmo-cp.wundergraph.com/openapi.json
    status: 404
    note: no provider-published OpenAPI at the control-plane host
  - url: https://cosmo-cp.wundergraph.com/v1/analytics
    status: 404
    note: REST path modeled in this document does not resolve
  - url: https://cosmo-cp.wundergraph.com/wg.cosmo.platform.v1.PlatformService/GetFederatedGraphs
    status: 200
    method: POST
    note: the surface that does exist — Connect-RPC, not REST