> ## Documentation Index
> Fetch the complete documentation index at: https://rollout.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Start a Cookie-Bound OAuth Grant

> For apps whose OAuth redirect doesn't carry `state` back: keeps the state in a cookie on this host and redirects to the app's authorization page. Opened by the URL `/oauth/authorize-url` returns.



## OpenAPI

````yaml /openapi/rollout.json get /auth/grant-start
openapi: 3.0.3
info:
  title: Universal API Documentation
  description: Development documentation
  version: '1.0'
servers:
  - url: https://universal.rollout.com/api
security: []
paths:
  /auth/grant-start:
    get:
      summary: Start a Cookie-Bound OAuth Grant
      description: >-
        For apps whose OAuth redirect doesn't carry `state` back: keeps the
        state in a cookie on this host and redirects to the app's authorization
        page. Opened by the URL `/oauth/authorize-url` returns.
      operationId: getAuthGrant-start
      parameters:
        - name: state
          in: query
          required: true
          schema:
            type: string
      responses:
        '302':
          description: A redirect to the app's authorization page
        '400':
          description: A page saying the link is invalid
          content:
            text/html:
              schema:
                type: string

````

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