Kimi API (All Models) - Messages Full Reference

curl --request POST \
  --url https://direct.evolink.ai/v1/messages \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "kimi-k3.1-pro",
  "max_tokens": 1024,
  "output_config": {
    "effort": "low"
  },
  "messages": [
    {
      "role": "user",
      "content": "Reply with OK."
    }
  ]
}
'

{
  "id": "<string>",
  "type": "message",
  "role": "assistant",
  "model": "kimi-k3.1-pro",
  "content": [
    {
      "type": "text",
      "text": "<string>"
    }
  ],
  "stop_reason": "end_turn",
  "stop_sequence": "<string>",
  "usage": {
    "input_tokens": 123,
    "cache_creation_input_tokens": 123,
    "cache_read_input_tokens": 123,
    "output_tokens": 123,
    "output_tokens_details": {
      "thinking_tokens": 123
    },
    "cache_creation": {
      "ephemeral_5m_input_tokens": 1,
      "ephemeral_1h_input_tokens": 1
    },
    "server_tool_use": {
      "web_search_requests": 1
    }
  }
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

POST

messages

curl --request POST \
  --url https://direct.evolink.ai/v1/messages \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "kimi-k3.1-pro",
  "max_tokens": 1024,
  "output_config": {
    "effort": "low"
  },
  "messages": [
    {
      "role": "user",
      "content": "Reply with OK."
    }
  ]
}
'

{
  "id": "<string>",
  "type": "message",
  "role": "assistant",
  "model": "kimi-k3.1-pro",
  "content": [
    {
      "type": "text",
      "text": "<string>"
    }
  ],
  "stop_reason": "end_turn",
  "stop_sequence": "<string>",
  "usage": {
    "input_tokens": 123,
    "cache_creation_input_tokens": 123,
    "cache_read_input_tokens": 123,
    "output_tokens": 123,
    "output_tokens_details": {
      "thinking_tokens": 123
    },
    "cache_creation": {
      "ephemeral_5m_input_tokens": 1,
      "ephemeral_1h_input_tokens": 1
    },
    "server_tool_use": {
      "web_search_requests": 1
    }
  }
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

{
  "type": "error",
  "error": {
    "type": "<string>",
    "message": "<string>"
  },
  "request_id": "<string>"
}

BaseURL: The default BaseURL is https://direct.evolink.ai, which has better support for text models and long-lived connections. https://api.evolink.ai is the primary endpoint for multimodal services and serves as a fallback address for text models.

Authorizations

Authorization

string

header

required

##All APIs require Bearer Token authentication##

Get API Key:

Visit API Key Management Page to get your API Key

Add to request header:

Authorization: Bearer YOUR_API_KEY

Body

application/json

model

enum<string>

default:kimi-k3.1-pro

required

Model to call:

Model ID	Positioning	Reasoning effort
`kimi-k3.1-pro`	Latest-generation model (recommended)	`low` / `high` / `max`, default `max`
`kimi-k3.1-pro-highspeed`	Same parameters as Pro, faster generation	Same as `kimi-k3.1-pro`
`kimi-k3`	Previous-generation model	Only `max`

All three models have a context window of 1,048,576 tokens and always have reasoning enabled.

Structured output (output_config.format), stop sequences (stop_sequences), and cache write TTL (cache_control) are supported only by the K3.1 series, not by kimi-k3. Responses from kimi-k3 may contain only text blocks without thinking blocks.

Available options:

kimi-k3.1-pro,

kimi-k3.1-pro-highspeed,

kimi-k3

max_tokens

integer

required

Maximum number of tokens allowed for this generation, including thinking and final text.

Required range: 1 <= x <= 1048576

messages

object[]

required

Anthropic Messages message list. For multi-turn conversations, return complete assistant content blocks unchanged.

Minimum array length: 1

Show child attributes

system

System prompt as a string or array of text blocks.

stream

boolean

default:false

Whether to return an Anthropic SSE event stream.

tools

object[]

Custom functions or server-side web search. Built-in search uses type=web_search_20250305 and name=web_search; billed per actual call.

Option 1
Option 2

Show child attributes

tool_choice

object

Show child attributes

stop_sequences

string[]

Stop sequences. Output stops on an exact match, and the matched sequence itself is omitted. Up to 5 sequences, each no more than 32 bytes. On a match, stop_reason is end_turn and stop_sequence is null.

Supported only by kimi-k3.1-pro / kimi-k3.1-pro-highspeed; kimi-k3 does not support this parameter.

Maximum array length: 5

cache_control

object

Top-level cache write options, supported only by kimi-k3.1-pro / kimi-k3.1-pro-highspeed; kimi-k3 does not support this parameter. Only top-level cache_control controls the write TTL; cache markers inside message blocks cannot replace this field. Defaults to 5m when omitted.

Show child attributes

output_config

object

Output configuration: reasoning effort and structured output.

Show child attributes

temperature

number

default:1

Sampling temperature, fixed by the model at 1; omit this field. kimi-k3.1-pro / kimi-k3.1-pro-highspeed automatically ignore it; kimi-k3 returns an error for unsupported values.

top_p

number

default:0.95

Nucleus sampling threshold, fixed by the model at 0.95; omit this field. kimi-k3.1-pro / kimi-k3.1-pro-highspeed automatically ignore it; kimi-k3 returns an error for unsupported values.

Response

Message response; streaming requests return an Anthropic SSE event stream

string

type

enum<string>

Available options:

message

role

enum<string>

Available options:

assistant

model

string

Example:

"kimi-k3.1-pro"

content

object[]

Anthropic content block for text, image, reasoning, tool use, or a tool result.

Show child attributes

stop_reason

enum<string> | null

Available options:

end_turn,

max_tokens,

tool_use,

refusal,

null

stop_sequence

string | null

usage

object

Show child attributes

Image Series

Video Series

Audio Series

Text Series

Account Management

Task Management

File Management

Kimi API (All Models) - Messages Full Reference

Authorizations

Body

Response