openapi: 3.0.3
info:
  title: GC AI External Chat Utility API
  version: 1.0.0
  description: 'The GC AI External API allows programmatic access to GC AI''s chat capabilities. It''s designed for integration with workflow automation tools like Zapier, Make, n8n, or custom applications.


    ## Authentication


    All API requests must include an API key in the `Authorization` header:


    ```

    Authorization: gcai_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

    ```


    API keys can be created in the GC AI app under **Settings → API**.


    ## Multi-turn Conversations


    Conversations can span multiple turns: pass the `chat_id` returned by a completion back on your next request to continue the same chat. See [Multi-turn Conversations](/api-reference/concepts/multi-turn).


    ## Current Limitations


    The following is not yet available via API:


    - **Interactive clarification**: the model cannot pause to ask the caller a follow-up question; the `askUserQuestions` tool is disabled on the API surface in beta


    ## Usage


    Usage is tracked and viewable in the GC AI app under **Settings → API → View Usage**.


    ## Support


    For API support, contact [support@gc.ai](mailto:support@gc.ai) or reach out to your account representative.'
  contact:
    email: support@gc.ai
servers:
- url: https://app.gc.ai/api/external/v1
  description: Production server
tags:
- name: Utility
  description: Health check and connectivity endpoints
paths:
  /ping:
    get:
      summary: Health check
      description: Returns a simple health check response. Useful for verifying API key validity and connectivity.
      operationId: ping
      tags:
      - Utility
      security:
      - ApiKeyAuth: []
      responses:
        '200':
          description: API is reachable and key is valid
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PingResponse'
        '401':
          description: Missing or malformed API key
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: Invalid API key
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded. See [Rate Limits](/api-reference/concepts/rate-limits) for the tiers, limits, and how to back off.
          headers:
            Retry-After:
              schema:
                type: string
                description: Seconds to wait before retrying after a rate-limit block.
                example: '60'
              required: true
              description: Seconds to wait before retrying after a rate-limit block.
            RateLimit-Limit:
              schema:
                type: string
                description: Request quota for the applicable window.
                example: '3'
              required: true
              description: Request quota for the applicable window.
            RateLimit-Remaining:
              schema:
                type: string
                description: Requests remaining in the current window.
                example: '0'
              required: true
              description: Requests remaining in the current window.
            RateLimit-Reset:
              schema:
                type: string
                description: Seconds until the quota resets.
                example: '60'
              required: true
              description: Seconds until the quota resets.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '503':
          description: Service temporarily unavailable
          headers:
            Retry-After:
              schema:
                type: string
                description: Seconds to wait before retrying after a transient service outage.
                example: '5'
              required: true
              description: Seconds to wait before retrying after a transient service outage.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    Error:
      type: object
      properties:
        error:
          type: string
          description: Error message
        code:
          type: string
          description: Machine-readable error code present on some errors (e.g. `RATE_LIMITED`, `INSUFFICIENT_CREDITS`, `TRIAL_NOT_STARTED`, `BILLING_NOT_CONFIGURED`). Branch on this rather than the human-readable `error` string.
        message:
          type: string
          description: Additional error details
        details:
          type: object
          additionalProperties:
            nullable: true
          description: Validation error details (for 400 errors)
      required:
      - error
    PingResponse:
      type: object
      properties:
        status:
          type: string
          enum:
          - pong
          description: Always `pong`
        timestamp:
          type: string
          description: ISO 8601 server timestamp
      required:
      - status
      - timestamp
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: Authorization
      description: 'API key for authentication. Format: `gcai_xxxxxxxxx`


        Create API keys in the GC AI app under Settings → API.'