> ## Documentation Index > Fetch the complete documentation index at: https://docs.modelslab.com/llms.txt > Use this file to discover all available pages before exploring further. # Messages > Anthropic-compatible messages endpoint. Works with the Anthropic SDK, Claude Code, and any Anthropic-compatible client. ## Request ```bash theme={null} POST https://modelslab.com/api/v7/llm/v1/messages ``` Pass your API key in the `x-api-key` header or as a Bearer token. ```bash theme={null} curl -X POST https://modelslab.com/api/v7/llm/v1/messages \ -H "x-api-key: $MODELSLAB_API_KEY" \ -H "Content-Type: application/json" \ -H "anthropic-version: 2023-06-01" \ -d '{ "model": "Qwen/Qwen2.5-VL-72B-Instruct-together", "max_tokens": 1024, "messages": [ {"role": "user", "content": "What is the capital of France?"} ] }' ``` ## Body ```json theme={null} { "model": "Qwen/Qwen2.5-VL-72B-Instruct-together", "max_tokens": 1024, "messages": [ {"role": "user", "content": "What is the capital of France?"} ], "system": "You are a helpful assistant.", "temperature": 0.7, "top_p": 1, "stream": false } ``` ## Response ```json theme={null} { "id": "msg_abc123", "type": "message", "role": "assistant", "content": [ { "type": "text", "text": "The capital of France is Paris." } ], "model": "Qwen/Qwen2.5-VL-72B-Instruct-together", "stop_reason": "end_turn", "usage": { "input_tokens": 15, "output_tokens": 8 } } ``` ## Streaming Set `"stream": true` to receive Server-Sent Events: ```bash theme={null} curl -X POST https://modelslab.com/api/v7/llm/v1/messages \ -H "x-api-key: $MODELSLAB_API_KEY" \ -H "Content-Type: application/json" \ -H "anthropic-version: 2023-06-01" \ -d '{ "model": "Qwen/Qwen2.5-VL-72B-Instruct-together", "max_tokens": 1024, "messages": [{"role": "user", "content": "Write a haiku"}], "stream": true }' ``` ## Anthropic SDK This endpoint is fully compatible with the Anthropic SDK. Just change the `base_url` and `api_key`: ```python theme={null} from anthropic import Anthropic client = Anthropic( api_key="YOUR_MODELSLAB_API_KEY", base_url="https://modelslab.com/api/v7/llm", ) # Non-streaming message = client.messages.create( model="Qwen/Qwen2.5-VL-72B-Instruct-together", max_tokens=1024, messages=[ {"role": "user", "content": "Explain quantum computing"} ], ) print(message.content[0].text) # Streaming with client.messages.stream( model="Qwen/Qwen2.5-VL-72B-Instruct-together", max_tokens=1024, messages=[{"role": "user", "content": "Write a story"}], ) as stream: for text in stream.text_stream: print(text, end="") ``` ```javascript theme={null} import Anthropic from '@anthropic-ai/sdk'; const client = new Anthropic({ apiKey: 'YOUR_MODELSLAB_API_KEY', baseURL: 'https://modelslab.com/api/v7/llm', }); const message = await client.messages.create({ model: 'Qwen/Qwen2.5-VL-72B-Instruct-together', max_tokens: 1024, messages: [ { role: 'user', content: 'Hello!' }, ], }); console.log(message.content[0].text); ``` ## Using with Claude Code You can use ModelsLab's LLM API as a backend for [Claude Code](https://claude.ai/claude-code), Anthropic's CLI coding assistant: ```bash theme={null} ANTHROPIC_BASE_URL="https://modelslab.com/api/v7/llm" \ ANTHROPIC_AUTH_TOKEN="YOUR_MODELSLAB_API_KEY" \ claude --model "Qwen/Qwen2.5-VL-72B-Instruct-together" ``` This lets you use any of ModelsLab's 200+ LLM models as the backend for Claude Code's agentic coding capabilities. ## OpenAPI ````yaml POST /v1/messages openapi: 3.1.0 info: title: ModelsLab LLM API description: >- Unified LLM API with OpenAI and Anthropic SDK compatibility. Access 200+ language models through a single API. version: 7.0.0 servers: [] security: [] paths: /v1/messages: post: summary: Messages description: >- Anthropic-compatible messages endpoint. Create messages and receive model responses in the Anthropic format. parameters: - name: anthropic-version in: header required: false schema: type: string default: '2023-06-01' description: Anthropic API version requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/MessagesRequest' responses: '200': description: Message response content: application/json: schema: $ref: '#/components/schemas/MessagesResponse' '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/Error' security: - apiKeyAuth: [] servers: - url: https://modelslab.com/api/v7/llm components: schemas: MessagesRequest: type: object required: - model - max_tokens - messages properties: model: type: string description: Model ID to use max_tokens: type: integer minimum: 1 description: Maximum number of tokens to generate messages: type: array description: Array of input messages items: $ref: '#/components/schemas/AnthropicMessage' system: type: string description: System prompt temperature: type: number minimum: 0 maximum: 1 default: 1 description: Sampling temperature top_p: type: number minimum: 0 maximum: 1 description: Nucleus sampling parameter stream: type: boolean default: false description: Whether to stream the response MessagesResponse: type: object properties: id: type: string description: Unique message ID type: type: string enum: - message role: type: string enum: - assistant content: type: array items: type: object properties: type: type: string enum: - text text: type: string model: type: string stop_reason: type: string enum: - end_turn - max_tokens - stop_sequence usage: $ref: '#/components/schemas/AnthropicUsage' Error: type: object properties: error: type: object properties: message: type: string type: type: string code: type: string AnthropicMessage: type: object required: - role - content properties: role: type: string enum: - user - assistant description: Role of the message sender content: type: string description: Content of the message AnthropicUsage: type: object properties: input_tokens: type: integer output_tokens: type: integer securitySchemes: apiKeyAuth: type: apiKey in: header name: x-api-key description: API key authentication via x-api-key header ````