openapi: 3.1.0 info: title: Moonshot AI Batch Chat API version: 1.0.0 description: API for Moonshot AI / Kimi large language model services servers: - url: https://api.moonshot.ai description: Production tags: - name: Chat paths: /v1/chat/completions: post: summary: Create Chat Completion description: Creates a completion for the chat message. Supports standard chat, Partial Mode, and Tool Use (Function Calling). tags: - Chat security: - bearerAuth: [] requestBody: required: true content: application/json: schema: oneOf: - $ref: '#/components/schemas/KimiK26ChatRequest' - $ref: '#/components/schemas/KimiK25ChatRequest' - $ref: '#/components/schemas/KimiK2ChatRequest' - $ref: '#/components/schemas/KimiK2ThinkingChatRequest' - $ref: '#/components/schemas/MoonshotV1ChatRequest' discriminator: propertyName: model mapping: kimi-k2.6: '#/components/schemas/KimiK26ChatRequest' kimi-k2.5: '#/components/schemas/KimiK25ChatRequest' kimi-k2-0905-preview: '#/components/schemas/KimiK2ChatRequest' kimi-k2-0711-preview: '#/components/schemas/KimiK2ChatRequest' kimi-k2-turbo-preview: '#/components/schemas/KimiK2ChatRequest' kimi-k2-thinking: '#/components/schemas/KimiK2ThinkingChatRequest' kimi-k2-thinking-turbo: '#/components/schemas/KimiK2ThinkingChatRequest' moonshot-v1-8k: '#/components/schemas/MoonshotV1ChatRequest' moonshot-v1-32k: '#/components/schemas/MoonshotV1ChatRequest' moonshot-v1-128k: '#/components/schemas/MoonshotV1ChatRequest' moonshot-v1-auto: '#/components/schemas/MoonshotV1ChatRequest' moonshot-v1-8k-vision-preview: '#/components/schemas/MoonshotV1ChatRequest' moonshot-v1-32k-vision-preview: '#/components/schemas/MoonshotV1ChatRequest' moonshot-v1-128k-vision-preview: '#/components/schemas/MoonshotV1ChatRequest' responses: '200': description: Chat completion response content: application/json: schema: $ref: '#/components/schemas/ChatCompletionResponse' '400': description: Bad request - Invalid parameters content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '401': description: Unauthorized - Invalid or missing API key content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '500': description: Server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' components: schemas: KimiK25ChatRequest: title: kimi-k2.5 allOf: - $ref: '#/components/schemas/ChatRequestBase' - type: object properties: model: type: string description: Model ID enum: - kimi-k2.5 default: kimi-k2.5 thinking: type: object description: 'Controls whether thinking is enabled for the model. Optional parameter. Default value is {"type": "enabled"}.' properties: type: type: string enum: - enabled - disabled description: Enable or disable thinking capability required: - type additionalProperties: false required: - model KimiK2ChatRequest: title: kimi-k2 allOf: - $ref: '#/components/schemas/ChatRequestBase' - type: object properties: model: type: string description: Model ID enum: - kimi-k2-0905-preview - kimi-k2-0711-preview - kimi-k2-turbo-preview default: kimi-k2-0905-preview temperature: type: number format: float description: The sampling temperature to use, ranging from 0 to 1. A higher value (e.g., 0.7) will make the output more random, while a lower value (e.g., 0.2) will make it more focused and deterministic. Default is 0.6. default: 0.6 minimum: 0 maximum: 1 top_p: type: number format: float description: Another sampling method, where the model considers the results of tokens with a cumulative probability mass of top_p. Thus, 0.1 means only considering the top 10% of tokens by probability mass. Generally, we suggest changing either this or the temperature, but not both at the same time. Default is 1.0. default: 1 minimum: 0 maximum: 1 n: type: integer description: The number of results to generate for each input message. Default is 1, must not exceed 5. When the temperature is very close to 0, only 1 result can be returned. default: 1 minimum: 1 maximum: 5 presence_penalty: type: number format: float description: Presence penalty, a number between -2.0 and 2.0. A positive value will penalize new tokens based on whether they appear in the text, increasing the likelihood of the model discussing new topics default: 0 minimum: -2 maximum: 2 frequency_penalty: type: number format: float description: Frequency penalty, a number between -2.0 and 2.0. A positive value will penalize new tokens based on their existing frequency in the text, reducing the likelihood of the model repeating the same phrases verbatim default: 0 minimum: -2 maximum: 2 required: - model ChatCompletionResponse: type: object properties: id: type: string description: Unique identifier for the completion object: type: string description: Object type example: chat.completion created: type: integer description: Unix timestamp of when the completion was created model: type: string description: Model used for the completion choices: type: array description: List of completion choices items: type: object properties: index: type: integer message: type: object properties: role: type: string enum: - assistant content: type: - string - 'null' description: The assistant's message content tool_calls: type: array description: Tool calls made by the model items: type: object properties: id: type: string type: type: string enum: - function function: type: object properties: name: type: string arguments: type: string description: JSON string of function arguments finish_reason: type: string enum: - stop - length - tool_calls usage: type: object properties: prompt_tokens: type: integer description: Number of tokens in the prompt completion_tokens: type: integer description: Number of tokens in the completion total_tokens: type: integer description: Total number of tokens used ErrorResponse: type: object properties: error: type: object properties: message: type: string description: Error message describing what went wrong type: type: string description: Error type code: type: string description: Error code required: - message required: - error ChatRequestBase: type: object properties: messages: type: array description: 'A list of messages in the conversation so far. Each element has the format {"role": "user", "content": "Hello"}. role supports system, user, or assistant. content must not be empty. The content field can be a string or an array[object] (for multimodal input).' items: $ref: '#/components/schemas/Message' max_tokens: type: integer deprecated: true description: Deprecated, please refer to max_completion_tokens max_completion_tokens: type: integer description: The maximum number of tokens to generate for the chat completion. If not specified, defaults to a reasonable integer such as 1024. If the result reaches the maximum number of tokens without ending, the finish reason will be "length"; otherwise, it will be "stop". This refers to the length of tokens you expect us to return, not the total length of input plus output. If input plus max_completion_tokens exceeds the model context window, the API returns invalid_request_error. response_format: type: object description: 'Controls the model output format. Default is {"type": "text"} for plain text output. Set to {"type": "json_object"} to enable JSON mode, ensuring output is a valid JSON object (you must guide the model to output JSON in the prompt). Set to {"type": "json_schema"} to enable Structured Output, constraining output to match a specified JSON Schema (recommended, requires the json_schema field). If you encounter schema validation issues, please submit feedback at walle GitHub Issues (https://github.com/MoonshotAI/walle/issues).' properties: type: type: string enum: - text - json_object - json_schema description: 'Output format type. text: default, plain text output; json_object: ensures output is a valid JSON object; json_schema: constrains output to match a specified JSON Schema (recommended, requires the json_schema field)' json_schema: type: object description: Used when type is json_schema. Defines the JSON Schema that the output should conform to. properties: name: type: string description: Schema name for identification strict: type: boolean default: true description: Whether to strictly constrain output according to the schema. Defaults to true. When true, the schema must conform to the MFJS specification; non-conforming schemas will return errors or warnings. When false, only guarantees the output is a valid JSON object without enforcing internal structure. schema: type: object description: 'The JSON Schema object defining the structure the output should conform to. Must conform to MFJS (Moonshot Flavored JSON Schema) specification. You can use the walle CLI tool to validate: go install github.com/moonshotai/walle/cmd/walle@latest && walle -schema ''your_schema'' -level strict' additionalProperties: true required: - name - schema stop: oneOf: - type: string - type: array items: type: string maxItems: 5 default: null description: Stop words, which will halt the output when a full match is found. The matched words themselves will not be output. A maximum of 5 strings is allowed, and each string must not exceed 32 bytes stream: type: boolean default: false description: Whether to return the response in a streaming fashion. Default is false. stream_options: type: object description: Options for streaming responses properties: include_usage: type: boolean default: false description: 'If set, an additional chunk will be streamed before the data: [DONE] message. The usage field on this chunk shows the token usage statistics for the entire request, and the choices field will always be an empty array. All other chunks will also include a usage field, but with a null value. NOTE: If the stream is interrupted, you may not receive the final usage chunk which contains the total token usage for the request' tools: type: array description: A list of tools the model may call items: $ref: '#/components/schemas/ToolDefinition' maxItems: 128 prompt_cache_key: type: string default: null description: Used to cache responses for similar requests to optimize cache hit rates. For Coding Agents, this is typically a session id or task id representing a single session; if the session is exited and later resumed, this value should remain the same. For Kimi Code Plan, this field is required to improve cache hit rates. For other agents involving multi-turn conversations, it is also recommended to implement this field safety_identifier: type: string description: A stable identifier used to help detect users of your application that may be violating usage policies. The ID should be a string that uniquely identifies each user. It is recommended to hash the username or email address to avoid sending any identifying information required: - messages KimiK2ThinkingChatRequest: title: kimi-k2-thinking allOf: - $ref: '#/components/schemas/ChatRequestBase' - type: object properties: model: type: string description: Model ID enum: - kimi-k2-thinking - kimi-k2-thinking-turbo default: kimi-k2-thinking temperature: type: number format: float description: The sampling temperature to use, ranging from 0 to 1. A higher value (e.g., 0.7) will make the output more random, while a lower value (e.g., 0.2) will make it more focused and deterministic. Default is 1.0. default: 1 minimum: 0 maximum: 1 top_p: type: number format: float description: Another sampling method, where the model considers the results of tokens with a cumulative probability mass of top_p. Thus, 0.1 means only considering the top 10% of tokens by probability mass. Generally, we suggest changing either this or the temperature, but not both at the same time. Default is 1.0. default: 1 minimum: 0 maximum: 1 n: type: integer description: The number of results to generate for each input message. Default is 1, must not exceed 5. When the temperature is very close to 0, only 1 result can be returned. default: 1 minimum: 1 maximum: 5 presence_penalty: type: number format: float description: Presence penalty, a number between -2.0 and 2.0. A positive value will penalize new tokens based on whether they appear in the text, increasing the likelihood of the model discussing new topics default: 0 minimum: -2 maximum: 2 frequency_penalty: type: number format: float description: Frequency penalty, a number between -2.0 and 2.0. A positive value will penalize new tokens based on their existing frequency in the text, reducing the likelihood of the model repeating the same phrases verbatim default: 0 minimum: -2 maximum: 2 required: - model ToolDefinition: type: object properties: type: type: string enum: - function function: type: object properties: name: type: string description: 'Function name. Must follow the regex: ^[a-zA-Z_][a-zA-Z0-9-_]{2,63}$' pattern: ^[a-zA-Z_][a-zA-Z0-9-_]{2,63}$ description: type: string description: Description of what the function does parameters: type: object description: Function parameters as JSON Schema. Must conform to the MFJS (Moonshot Flavored JSON Schema) specification additionalProperties: true strict: type: boolean default: true description: Whether to strictly constrain tool call arguments according to the parameters schema. Defaults to true. When false, only guarantees the output is a valid JSON object without enforcing internal structure. required: - name - parameters required: - type - function KimiK26ChatRequest: title: kimi-k2.6 allOf: - $ref: '#/components/schemas/ChatRequestBase' - type: object properties: model: type: string description: Model ID enum: - kimi-k2.6 default: kimi-k2.6 thinking: type: object description: 'Controls whether thinking is enabled for the kimi-k2.6 model, and whether to fully preserve reasoning_content across multi-turn conversations. Optional parameter. Default value is {"type": "enabled"}.' properties: type: type: string enum: - enabled - disabled description: Enable or disable thinking capability keep: type: - string - 'null' enum: - all - null description: 'Controls whether reasoning_content from previous turns is preserved across a multi-turn conversation, i.e. whether to enable Preserved Thinking. Defaults to `null`, meaning historical thinking is NOT preserved. - `null` (default) or omitted: The server ignores reasoning_content from historical turns. - `"all"`: Preserves reasoning_content from historical turns and provides it to the model as part of the context, enabling Preserved Thinking. When using this, keep the reasoning_content from every historical assistant message in messages as-is. Recommended to use together with `type: "enabled"`. - Note: This parameter only affects reasoning_content from historical turns; it does not change whether the model produces/outputs thinking within the current turn (that is controlled by `type`). For best practices, see [Preserved Thinking](/guide/use-kimi-k2-thinking-model#preserved-thinking).' required: - type additionalProperties: false required: - model MoonshotV1ChatRequest: title: moonshot-v1 allOf: - $ref: '#/components/schemas/ChatRequestBase' - type: object properties: model: type: string description: Model ID enum: - moonshot-v1-8k - moonshot-v1-32k - moonshot-v1-128k - moonshot-v1-auto - moonshot-v1-8k-vision-preview - moonshot-v1-32k-vision-preview - moonshot-v1-128k-vision-preview default: moonshot-v1-128k temperature: type: number format: float description: The sampling temperature to use, ranging from 0 to 1. A higher value (e.g., 0.7) will make the output more random, while a lower value (e.g., 0.2) will make it more focused and deterministic. Default is 0.0. default: 0 minimum: 0 maximum: 1 top_p: type: number format: float description: Another sampling method, where the model considers the results of tokens with a cumulative probability mass of top_p. Thus, 0.1 means only considering the top 10% of tokens by probability mass. Generally, we suggest changing either this or the temperature, but not both at the same time. Default is 1.0. default: 1 minimum: 0 maximum: 1 n: type: integer description: The number of results to generate for each input message. Default is 1, must not exceed 5. When the temperature is very close to 0, only 1 result can be returned. default: 1 minimum: 1 maximum: 5 presence_penalty: type: number format: float description: Presence penalty, a number between -2.0 and 2.0. A positive value will penalize new tokens based on whether they appear in the text, increasing the likelihood of the model discussing new topics default: 0 minimum: -2 maximum: 2 frequency_penalty: type: number format: float description: Frequency penalty, a number between -2.0 and 2.0. A positive value will penalize new tokens based on their existing frequency in the text, reducing the likelihood of the model repeating the same phrases verbatim default: 0 minimum: -2 maximum: 2 required: - model Message: type: object properties: role: type: string enum: - system - user - assistant description: The role of the message sender content: oneOf: - type: string - type: array items: oneOf: - title: text type: object properties: type: type: string enum: - text text: type: string required: - type - text - title: image_url type: object properties: type: type: string enum: - image_url image_url: oneOf: - type: object properties: url: type: string required: - url - type: string required: - type - image_url - title: video_url type: object properties: type: type: string enum: - video_url video_url: oneOf: - type: object properties: url: type: string required: - url - type: string required: - type - video_url description: The content of the message. Can be a plain text string, or an array of objects with text/image_url/video_url types (for multimodal input) name: type: string default: null description: Optional name for the message sender partial: type: boolean default: false description: Enable Partial Mode by setting this to true in the last assistant message required: - role - content securitySchemes: bearerAuth: type: http scheme: bearer description: The Authorization header expects a Bearer token. Use an MOONSHOT_API_KEY as the token. This is a server-side secret key. Generate one on the [API keys page](https://platform.kimi.ai/console/api-keys) in your dashboard.