> ## Documentation Index > Fetch the complete documentation index at: https://docs.ollama.com/llms.txt > Use this file to discover all available pages before exploring further. # Generate a chat message > Generate the next chat message in a conversation between a user and an assistant. ## OpenAPI ````yaml /openapi.yaml post /api/chat openapi: 3.1.0 info: title: Ollama API version: 0.1.0 license: name: MIT url: https://opensource.org/licenses/MIT description: | OpenAPI specification for the Ollama HTTP API servers: - url: http://localhost:11434 description: Ollama security: [] paths: /api/chat: post: summary: Generate a chat message description: >- Generate the next chat message in a conversation between a user and an assistant. operationId: chat requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ChatRequest' responses: '200': description: Chat response content: application/json: schema: $ref: '#/components/schemas/ChatResponse' example: model: gemma3 created_at: '2025-10-17T23:14:07.414671Z' message: role: assistant content: Hello! How can I help you today? done: true done_reason: stop total_duration: 174560334 load_duration: 101397084 prompt_eval_count: 11 prompt_eval_duration: 13074791 eval_count: 18 eval_duration: 52479709 application/x-ndjson: schema: $ref: '#/components/schemas/ChatStreamEvent' x-codeSamples: - lang: bash label: Default source: | curl http://localhost:11434/api/chat -d '{ "model": "gemma3", "messages": [ { "role": "user", "content": "why is the sky blue?" } ] }' - lang: bash label: Non-streaming source: | curl http://localhost:11434/api/chat -d '{ "model": "gemma3", "messages": [ { "role": "user", "content": "why is the sky blue?" } ], "stream": false }' - lang: bash label: Structured outputs source: > curl -X POST http://localhost:11434/api/chat -H "Content-Type: application/json" -d '{ "model": "gemma3", "messages": [ { "role": "user", "content": "What are the populations of the United States and Canada?" } ], "stream": false, "format": { "type": "object", "properties": { "countries": { "type": "array", "items": { "type": "object", "properties": { "country": {"type": "string"}, "population": {"type": "integer"} }, "required": ["country", "population"] } } }, "required": ["countries"] } }' - lang: bash label: Tool calling source: | curl http://localhost:11434/api/chat -d '{ "model": "qwen3", "messages": [ { "role": "user", "content": "What is the weather today in Paris?" } ], "stream": false, "tools": [ { "type": "function", "function": { "name": "get_current_weather", "description": "Get the current weather for a location", "parameters": { "type": "object", "properties": { "location": { "type": "string", "description": "The location to get the weather for, e.g. San Francisco, CA" }, "format": { "type": "string", "description": "The format to return the weather in, e.g. 'celsius' or 'fahrenheit'", "enum": ["celsius", "fahrenheit"] } }, "required": ["location", "format"] } } } ] }' - lang: bash label: Thinking source: | curl http://localhost:11434/api/chat -d '{ "model": "gpt-oss", "messages": [ { "role": "user", "content": "What is 1+1?" } ], "think": "low" }' - lang: bash label: Images source: | curl http://localhost:11434/api/chat -d '{ "model": "gemma3", "messages": [ { "role": "user", "content": "What is in this image?", "images": [ "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" ] } ] }' components: schemas: ChatRequest: type: object required: - model - messages properties: model: type: string description: Model name messages: type: array description: >- Chat history as an array of message objects (each with a role and content) items: $ref: '#/components/schemas/ChatMessage' tools: type: array description: Optional list of function tools the model may call during the chat items: $ref: '#/components/schemas/ToolDefinition' format: oneOf: - type: string enum: - json - type: object description: Format to return a response in. Can be `json` or a JSON schema options: $ref: '#/components/schemas/ModelOptions' stream: type: boolean default: true think: oneOf: - type: boolean - type: string enum: - high - medium - low description: >- When true, returns separate thinking output in addition to content. Can be a boolean (true/false) or a string ("high", "medium", "low") for supported models. keep_alive: oneOf: - type: string - type: number description: >- Model keep-alive duration (for example `5m` or `0` to unload immediately) logprobs: type: boolean description: Whether to return log probabilities of the output tokens top_logprobs: type: integer description: >- Number of most likely tokens to return at each token position when logprobs are enabled ChatResponse: type: object properties: model: type: string description: Model name used to generate this message created_at: type: string format: date-time description: Timestamp of response creation (ISO 8601) message: type: object properties: role: type: string enum: - assistant description: Always `assistant` for model responses content: type: string description: Assistant message text thinking: type: string description: Optional deliberate thinking trace when `think` is enabled tool_calls: type: array items: $ref: '#/components/schemas/ToolCall' description: Tool calls requested by the assistant images: type: array items: type: string description: Optional base64-encoded images in the response done: type: boolean description: Indicates whether the chat response has finished done_reason: type: string description: Reason the response finished total_duration: type: integer description: Total time spent generating in nanoseconds load_duration: type: integer description: Time spent loading the model in nanoseconds prompt_eval_count: type: integer description: Number of tokens in the prompt prompt_eval_duration: type: integer description: Time spent evaluating the prompt in nanoseconds eval_count: type: integer description: Number of tokens generated in the response eval_duration: type: integer description: Time spent generating tokens in nanoseconds logprobs: type: array items: $ref: '#/components/schemas/Logprob' description: >- Log probability information for the generated tokens when logprobs are enabled ChatStreamEvent: type: object properties: model: type: string description: Model name used for this stream event created_at: type: string format: date-time description: When this chunk was created (ISO 8601) message: type: object properties: role: type: string description: Role of the message for this chunk content: type: string description: Partial assistant message text thinking: type: string description: Partial thinking text when `think` is enabled tool_calls: type: array items: $ref: '#/components/schemas/ToolCall' description: Partial tool calls, if any images: type: array items: type: string description: Partial base64-encoded images, when present done: type: boolean description: True for the final event in the stream ChatMessage: type: object required: - role - content properties: role: type: string enum: - system - user - assistant - tool description: Author of the message. content: type: string description: Message text content images: type: array items: type: string description: Base64-encoded image content description: Optional list of inline images for multimodal models tool_calls: type: array items: $ref: '#/components/schemas/ToolCall' description: Tool call requests produced by the model ToolDefinition: type: object required: - type - function properties: type: type: string enum: - function description: Type of tool (always `function`) function: type: object required: - name - parameters properties: name: type: string description: Function name exposed to the model description: type: string description: Human-readable description of the function parameters: type: object description: JSON Schema for the function parameters ModelOptions: type: object description: Runtime options that control text generation properties: seed: type: integer description: Random seed used for reproducible outputs temperature: type: number format: float description: Controls randomness in generation (higher = more random) top_k: type: integer description: Limits next token selection to the K most likely top_p: type: number format: float description: Cumulative probability threshold for nucleus sampling min_p: type: number format: float description: Minimum probability threshold for token selection stop: oneOf: - type: string - type: array items: type: string description: Stop sequences that will halt generation num_ctx: type: integer description: Context length size (number of tokens) num_predict: type: integer description: Maximum number of tokens to generate additionalProperties: true ToolCall: type: object properties: function: type: object required: - name properties: name: type: string description: Name of the function to call description: type: string description: What the function does arguments: type: object description: JSON object of arguments to pass to the function Logprob: type: object description: Log probability information for a generated token properties: token: type: string description: The text representation of the token logprob: type: number description: The log probability of this token bytes: type: array items: type: integer description: The raw byte representation of the token top_logprobs: type: array items: $ref: '#/components/schemas/TokenLogprob' description: Most likely tokens and their log probabilities at this position TokenLogprob: type: object description: Log probability information for a single token alternative properties: token: type: string description: The text representation of the token logprob: type: number description: The log probability of this token bytes: type: array items: type: integer description: The raw byte representation of the token ````