> ## Documentation Index > Fetch the complete documentation index at: https://docs.antarah.dev/llms.txt > Use this file to discover all available pages before exploring further. # Count tokens ## OpenAPI ````yaml POST /v1/messages/count_tokens openapi: 3.1.0 info: title: Antara API version: 1.0.0 description: OpenAI- and Anthropic-compatible inference plus organization management. servers: - url: https://api.antarah.dev security: [] paths: /v1/messages/count_tokens: post: summary: >- Count a Messages request's input tokens (cached 10 min by body; not billed; counts toward RPM only) requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CountTokensRequest' responses: '200': description: OK headers: x-request-id: schema: type: string description: Request ID (`req_…`); also sent as `request-id` required: false description: Request ID (`req_…`); also sent as `request-id` ratelimit-policy: schema: type: string description: e.g. `"rpm";q=60;w=60` (02 §8) required: false description: e.g. `"rpm";q=60;w=60` (02 §8) ratelimit: schema: type: string description: Scope closest to exhaustion, e.g. `"rpm";r=59;t=42` required: false description: Scope closest to exhaustion, e.g. `"rpm";r=59;t=42` content: application/json: schema: $ref: '#/components/schemas/CountTokens' '404': description: '`model_not_found`' content: application/json: schema: $ref: '#/components/schemas/AnthropicError' '502': description: '`upstream_error`' content: application/json: schema: $ref: '#/components/schemas/AnthropicError' '503': description: '`upstream_unavailable`' content: application/json: schema: $ref: '#/components/schemas/AnthropicError' '504': description: '`upstream_timeout`' content: application/json: schema: $ref: '#/components/schemas/AnthropicError' default: description: Anthropic-shaped error (02 §4.1) content: application/json: schema: $ref: '#/components/schemas/AnthropicError' security: - projectKey: [] - session: [] components: schemas: CountTokensRequest: type: object properties: model: type: string minLength: 1 description: Public model ID, e.g. `a1` (A-05) example: a1 messages: type: array items: oneOf: - type: object properties: role: type: string enum: - user content: anyOf: - type: string - type: array items: oneOf: - type: object properties: type: type: string enum: - text text: type: string minLength: 1 required: - type - text - type: object properties: type: type: string enum: - image source: oneOf: - type: object properties: type: type: string enum: - base64 media_type: type: string enum: - image/png - image/jpeg - image/webp - image/gif data: type: string required: - type - media_type - data - type: object properties: type: type: string enum: - url url: type: string required: - type - url required: - type - source - type: object properties: type: type: string enum: - tool_result tool_use_id: type: string minLength: 1 content: anyOf: - type: string - type: array items: oneOf: - type: object properties: type: type: string enum: - text text: type: string minLength: 1 required: - type - text - type: object properties: type: type: string enum: - image source: oneOf: - type: object properties: type: type: string enum: - base64 media_type: type: string enum: - image/png - image/jpeg - image/webp - image/gif data: type: string required: - type - media_type - data - type: object properties: type: type: string enum: - url url: type: string required: - type - url required: - type - source is_error: type: boolean required: - type - tool_use_id - type: object properties: type: type: string enum: - document required: - type - type: object properties: type: type: string enum: - search_result required: - type minItems: 1 required: - role - content - type: object properties: role: type: string enum: - assistant content: anyOf: - type: string - type: array items: oneOf: - type: object properties: type: type: string enum: - text text: type: string minLength: 1 required: - type - text - type: object properties: type: type: string enum: - tool_use id: type: string minLength: 1 name: type: string minLength: 1 input: type: object additionalProperties: {} required: - type - id - name - input - type: object properties: type: type: string enum: - thinking thinking: type: string signature: type: string required: - type - thinking - type: object properties: type: type: string enum: - redacted_thinking data: type: string required: - type - data required: - role - content minItems: 1 maxItems: 10000 system: anyOf: - type: string - type: array items: type: object properties: type: type: string enum: - text text: type: string minLength: 1 required: - type - text tools: type: array items: type: object properties: type: type: string name: type: string minLength: 1 description: type: string input_schema: type: object additionalProperties: {} required: - name maxItems: 128 tool_choice: oneOf: - type: object properties: type: type: string enum: - auto disable_parallel_tool_use: type: boolean required: - type - type: object properties: type: type: string enum: - any disable_parallel_tool_use: type: boolean required: - type - type: object properties: type: type: string enum: - none required: - type - type: object properties: type: type: string enum: - tool name: type: string minLength: 1 disable_parallel_tool_use: type: boolean required: - type - name thinking: anyOf: - type: boolean enum: - false - type: object properties: type: type: string enum: - enabled budget_tokens: type: integer minimum: 1 required: - type - budget_tokens - type: object properties: type: type: string enum: - disabled required: - type required: - model - messages additionalProperties: false CountTokens: type: object properties: input_tokens: type: integer required: - input_tokens AnthropicError: type: object properties: type: type: string enum: - error error: type: object properties: type: type: string example: invalid_request_error message: type: string code: type: string required: - type - message - code request_id: type: string required: - type - error - request_id securitySchemes: projectKey: type: http scheme: bearer description: '`ak_…` project API key (or `x-api-key`)' session: type: http scheme: bearer bearerFormat: JWT description: >- Supabase access token + `Antara-Organization` (management) or `Antara-Project` (inference) ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.