Skip to main content
POST
/
v1
/
chat
/
completions
Create Chat Completion
curl --request POST \
  --url https://api.moonshot.ai/v1/chat/completions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "messages": [
    {
      "role": "system",
      "content": "<string>",
      "name": null,
      "partial": false
    }
  ],
  "model": "kimi-k2.6"
}
'
{
  "id": "<string>",
  "object": "chat.completion",
  "created": 123,
  "model": "<string>",
  "choices": [
    {
      "index": 123,
      "message": {
        "role": "assistant",
        "content": "<string>",
        "tool_calls": [
          {
            "id": "<string>",
            "type": "function",
            "function": {
              "name": "<string>",
              "arguments": "<string>"
            }
          }
        ]
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 123,
    "completion_tokens": 123,
    "total_tokens": 123
  }
}

Documentation Index

Fetch the complete documentation index at: https://platform.kimi.ai/docs/llms.txt

Use this file to discover all available pages before exploring further.

Create a chat completion request. The model generates a response based on the provided message list.
The content field supports the following two forms:Plain text string
"content": "Hello"
Array of objects (for multimodal input)Each element in the array is distinguished by the type field:
"content": [
    { "type": "text", "text": "Describe this image" },
    { "type": "image_url", "image_url": { "url": "data:image/png;base64,..." } },
    { "type": "video_url", "video_url": { "url": "data:video/mp4;base64,..." } }
]
image_url and video_url also support passing a string directly, equivalent to the url field in object form:
{ "type": "image_url", "image_url": "data:image/png;base64,..." }

​
Parameter Description

Each element in the array has the following fields:
ParameterRequiredDescriptionType
typerequiredContent type"text" | "image_url" | "video_url"
textrequired when type=textText contentstring
image_urlrequired when type=image_urlFor transmitting images. Supports object form {"url": "..."} or a URL string directlyobject | string
video_urlrequired when type=video_urlFor transmitting videos. Supports object form {"url": "..."} or a URL string directlyobject | string
When image_url is passed as an object, its fields are:
ParameterRequiredDescriptionType
urlrequiredImage content specified via base64 encoding or file idstring
When video_url is passed as an object, its fields are:
ParameterRequiredDescriptionType
urlrequiredVideo content specified via base64 encoding or file id, for example data:video/mp4;base64,...string
Both the object form (url field) and the string shorthand support the following formats:
  • Base64 encoding: data:image/png;base64,... or data:video/mp4;base64,...
  • File reference: ms://<file_id>
See Use the Kimi Vision Model.

​
Usage Example

import os
import base64

from openai import OpenAI
from openai.types.chat import ChatCompletion

client: OpenAI = OpenAI(
    api_key=os.environ.get("MOONSHOT_API_KEY"),
    base_url="https://api.moonshot.ai/v1",
)

# Encode the image to base64
with open("your_image_path", "rb") as f:
    img_base: str = base64.b64encode(f.read()).decode("utf-8")

response: ChatCompletion = client.chat.completions.create(
    model="kimi-k2.6",
    messages=[
        {
            "role": "user",
            "content": [
                {
                    "type": "image_url",
                    "image_url": {
                        "url": f"data:image/jpeg;base64,{img_base}",
                    },
                },
                {
                    "type": "text",
                    "text": "Describe this image",
                },
            ],
        }
    ],
)
print(response.choices[0].message.content)

​
Non-streaming Response

{
    "id": "cmpl-04ea926191a14749b7f2c7a48a68abc6",
    "object": "chat.completion",
    "created": 1698999496,
    "model": "kimi-k2.6",
    "choices": [
        {
            "index": 0,
            "message": {
                "role": "assistant",
                "content": "Hello, Li Lei! 1+1 equals 2. If you have any other questions, feel free to ask!"
            },
            "finish_reason": "stop"
        }
    ],
    "usage": {
        "prompt_tokens": 19,
        "completion_tokens": 21,
        "total_tokens": 40,
        "cached_tokens": 10
    }
}

​
Streaming Response

data: {"id":"cmpl-xxx","object":"chat.completion.chunk","created":1698999575,"model":"kimi-k2.6","choices":[{"index":0,"delta":{"role":"assistant","content":""},"finish_reason":null}]}

data: {"id":"cmpl-xxx","object":"chat.completion.chunk","created":1698999575,"model":"kimi-k2.6","choices":[{"index":0,"delta":{"content":"Hello"},"finish_reason":null}]}

...

data: {"id":"cmpl-xxx","object":"chat.completion.chunk","created":1698999575,"model":"kimi-k2.6","choices":[{"index":0,"delta":{},"finish_reason":"stop","usage":{"prompt_tokens":19,"completion_tokens":13,"total_tokens":32}}]}

data: [DONE]
The model name in the response example will be returned based on the model parameter in the request. When using the kimi-k2.6 model, the "model" field in the response will show "kimi-k2.6".

Authorizations

​
Authorization
string
header
required

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 in your dashboard.

Body

application/json
​
messages
object[]
required

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).

​
model
enum<string>
default:kimi-k2.6
required

Model ID

Available options:
kimi-k2.6
​
max_tokens
integer
deprecated

Deprecated, please refer to max_completion_tokens

​
max_completion_tokens
integer

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
object

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).

​
stop

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
boolean
default:false

Whether to return the response in a streaming fashion. Default is false.

​
stream_options
object

Options for streaming responses

​
tools
object[]

A list of tools the model may call

Maximum array length: 128
​
prompt_cache_key
string

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
string

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

​
thinking
object

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"}.

Response

Chat completion response

​
id
string

Unique identifier for the completion

​
object
string

Object type

Example:

"chat.completion"

​
created
integer

Unix timestamp of when the completion was created

​
model
string

Model used for the completion

​
choices
object[]

List of completion choices

​
usage
object