> ## Documentation Index > Fetch the complete documentation index at: https://runcrate.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # Responses (OpenAI-compatible) > The OpenAI Responses API, so Codex and `responses.create` work with a Runcrate key and Runcrate model ids. Same billing, limits and models as chat completions. Nothing is stored: `previous_response_id`, `conversation` and `background` answer 400, and hosted tools (web_search, file_search, ...) are left out. ## OpenAPI ````yaml /api-reference/openapi.json post /responses openapi: 3.1.0 info: title: Runcrate API version: 1.0.0 summary: OpenAI-compatible inference API + GPU infrastructure API. description: >- Runcrate exposes two API surfaces. The inference API at `https://api.runcrate.ai/v1` is OpenAI-compatible: it accepts the standard OpenAI SDK with the base URL changed. The infrastructure API at `https://www.runcrate.ai/api/v1` manages GPU instances, jobs, persistent volumes, environments, SSH keys, templates, and billing. Both share a single `rc_live_*` API key. Pricing is per-token, per-image, per-second, or per-minute on the inference API (varies by model; see https://www.runcrate.ai/api/models/catalog for live rates) and per-second on GPU rentals (see https://www.runcrate.ai/pricing for hourly rates per GPU class). All infrastructure API responses are wrapped in `{ "data": ... }`. List responses also include a `meta` object with pagination cursors. Error responses use `{ "error": { "code": "...", "message": "..." } }`. termsOfService: https://www.runcrate.ai/terms contact: name: Runcrate url: https://www.runcrate.ai/contact license: name: Proprietary url: https://www.runcrate.ai/terms servers: - url: https://api.runcrate.ai/v1 description: Inference API (OpenAI-compatible) - url: https://www.runcrate.ai/api/v1 description: >- Infrastructure API (instances, jobs, storage, environments, ssh-keys, templates, billing) security: - ApiKeyAuth: [] tags: - name: Chat description: OpenAI-compatible chat completions. - name: Messages description: Anthropic-compatible Messages API, for Claude Code and the Anthropic SDKs. - name: Responses description: >- OpenAI-compatible Responses API, for Codex and responses.create. Nothing is stored. - name: Images description: Text-to-image generation. - name: Videos description: Async text-to-video and image-to-video generation. - name: Audio description: Text-to-speech and speech-to-text. - name: Embeddings description: Vector embeddings for RAG and search. - name: Models description: Model catalog discovery. - name: Instances description: GPU instance lifecycle. - name: Jobs description: >- Run one command on its own GPU machine. The machine stops, and billing ends, when the command exits. - name: Schedules description: >- Start an instance or a job later: once at a set time, or on a repeating cron schedule in your timezone. - name: Storage description: Persistent volume management. - name: Environments description: Resource isolation containers within a workspace. - name: Secrets description: >- Names of the secrets an environment's machines get. Values are set in the dashboard and never returned. - name: SSH Keys description: SSH key management for instance access. - name: Templates description: Pre-built instance images and configurations. - name: Billing description: Credit balance, transactions, usage metrics. paths: /responses: post: tags: - Responses summary: Responses (OpenAI-compatible) description: >- The OpenAI Responses API, so Codex and `responses.create` work with a Runcrate key and Runcrate model ids. Same billing, limits and models as chat completions. Nothing is stored: `previous_response_id`, `conversation` and `background` answer 400, and hosted tools (web_search, file_search, ...) are left out. operationId: createResponse requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ResponsesRequest' responses: '200': description: >- A response object (or an SSE stream of response.* events when stream=true). content: application/json: schema: type: object description: >- A Response: id, object, status, output (reasoning, message, function_call and custom_tool_call items) and usage. text/event-stream: schema: type: string description: >- response.created, response.in_progress, response.output_item.added and .done, content parts, text, reasoning summary and function call argument deltas, then response.completed, response.incomplete or response.failed. '401': $ref: '#/components/responses/Unauthorized' '402': $ref: '#/components/responses/PaymentRequired' '429': $ref: '#/components/responses/RateLimited' components: schemas: ResponsesRequest: type: object required: - model - input properties: model: type: string description: A Runcrate model id (e.g. `zai-org/GLM-5.3`). instructions: type: string input: oneOf: - type: string - type: array items: type: object description: >- A string, or message, function_call, function_call_output, custom_tool_call and custom_tool_call_output items. reasoning items are accepted and not passed to the model. tools: type: array description: function, custom and namespace tools. items: type: object tool_choice: oneOf: - type: string enum: - auto - none - required - type: object parallel_tool_calls: type: boolean max_output_tokens: type: integer minimum: 1 temperature: type: number top_p: type: number reasoning: type: object description: >- `effort`: minimal and low are low, medium medium, high and xhigh high. text: type: object description: '`format`: text, json_object or json_schema.' prompt_cache_key: type: string stream: type: boolean default: false store: type: boolean description: Accepted; nothing is stored. Error: type: object required: - error properties: error: type: object required: - code - message properties: code: type: string description: >- Machine-readable error code (e.g. `validation_error`, `unauthorized`, `not_found`, `insufficient_credits`, `rate_limited`, `internal_error`). message: type: string description: Human-readable error message. details: type: object additionalProperties: true description: Optional structured error context. responses: Unauthorized: description: Missing or invalid API key. content: application/json: schema: $ref: '#/components/schemas/Error' PaymentRequired: description: >- Insufficient credits, the environment has reached its monthly budget (error code `BUDGET_REACHED`), or launches are paused while a payment on the workspace is disputed (`PAYMENT_HOLD`). content: application/json: schema: $ref: '#/components/schemas/Error' RateLimited: description: Rate limited. Retry with exponential backoff. content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: ApiKeyAuth: type: http scheme: bearer description: >- Use a Runcrate API key with the `rc_live_*` prefix as the bearer token. Create one at https://www.runcrate.ai/dashboard/api-keys. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.