> ## Documentation Index
> Fetch the complete documentation index at: https://docs.z.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Chat Completion
> Create a chat completion model that generates AI replies for given conversation messages. It supports multimodal inputs (text, images, audio, video, file), offers configurable parameters (like temperature, max tokens, tool use), and supports both streaming and non-streaming output modes.
## OpenAPI
````yaml POST /paas/v4/chat/completions
openapi: 3.0.1
info:
title: Z.AI API
description: Z.AI API available endpoints
license:
name: Z.AI Developer Agreement and Policy
url: https://chat.z.ai/legal-agreement/terms-of-service
version: 1.0.0
contact:
name: Z.AI Developers
url: https://chat.z.ai/legal-agreement/privacy-policy
email: user_feedback@z.ai
servers:
- url: https://api.z.ai/api
description: Production server
security:
- bearerAuth: []
paths:
/paas/v4/chat/completions:
post:
description: >-
Create a chat completion model that generates AI replies for given
conversation messages. It supports multimodal inputs (text, images,
audio, video, file), offers configurable parameters (like temperature,
max tokens, tool use), and supports both streaming and non-streaming
output modes.
parameters:
- $ref: '#/components/parameters/AcceptLanguage'
requestBody:
content:
application/json:
schema:
oneOf:
- $ref: '#/components/schemas/ChatCompletionTextRequest'
title: Text Model
- $ref: '#/components/schemas/ChatCompletionVisionRequest'
title: Vision Model
examples:
Basic Example:
value:
model: glm-5.1
messages:
- role: system
content: You are a useful AI assistant.
- role: user
content: >-
Please tell us about the development of artificial
intelligence.
temperature: 1
stream: false
Stream Example:
value:
model: glm-5.1
messages:
- role: user
content: Write a poem about spring.
temperature: 1
stream: true
Thinking Example:
value:
model: glm-5.1
messages:
- role: user
content: Write a poem about spring.
thinking:
type: enabled
stream: true
Multi Conversation:
value:
model: glm-5.1
messages:
- role: system
content: You are a professional programming assistant.
- role: user
content: What is recursion?
- role: assistant
content: >-
Recursion is a programming technique where a function
calls itself to solve a problem... What is recursion
- role: user
content: Can you give me an example of Python recursion?
stream: true
Image Visual Example:
value:
model: glm-5v-turbo
messages:
- role: user
content:
- type: image_url
image_url:
url: https://cdn.bigmodel.cn/static/logo/register.png
- type: image_url
image_url:
url: https://cdn.bigmodel.cn/static/logo/api-key.png
- type: text
text: What are the pics talk about?
Video Visual Example:
value:
model: glm-5v-turbo
messages:
- role: user
content:
- type: video_url
video_url:
url: >-
https://cdn.bigmodel.cn/agent-demos/lark/113123.mov
- type: text
text: What are the video show about?
File Visual Example:
value:
model: glm-5v-turbo
messages:
- role: user
content:
- type: file_url
file_url:
url: https://cdn.bigmodel.cn/static/demo/demo2.txt
- type: file_url
file_url:
url: https://cdn.bigmodel.cn/static/demo/demo1.pdf
- type: text
text: What are the files show about?
Function Call Example:
value:
model: glm-5.1
messages:
- role: user
content: >-
Is there an example of how the weather in Beijing is
today?
tools:
- type: function
function:
name: get_weather
description: Get weather information for the specified city.
parameters:
type: object
properties:
city:
type: string
description: City Name
required:
- city
tool_choice: auto
temperature: 0.3
required: true
responses:
'200':
description: Processing successful
content:
application/json:
schema:
$ref: '#/components/schemas/ChatCompletionResponse'
default:
description: The request has failed.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
components:
parameters:
AcceptLanguage:
name: Accept-Language
in: header
schema:
type: string
description: Config desired response language for HTTP requests.
default: en-US,en
example: en-US,en
enum:
- en-US,en
required: false
schemas:
ChatCompletionTextRequest:
required:
- model
- messages
type: object
properties:
model:
type: string
description: >-
The model code to be called. GLM-5.1, GLM-5, GLM-5-Turbo are the
latest flagship model series, foundational models specifically
designed for agent applications.
example: glm-5.1
default: glm-5.1
enum:
- glm-5.1
- glm-5-turbo
- glm-5
- glm-4.7
- glm-4.7-flash
- glm-4.7-flashx
- glm-4.6
- glm-4.5
- glm-4.5-air
- glm-4.5-x
- glm-4.5-airx
- glm-4.5-flash
- glm-4-32b-0414-128k
messages:
type: array
description: >-
The current conversation message list as the model’s prompt input,
provided in JSON array format, e.g.,`{“role”: “user”, “content”:
“Hello”}`. Possible message types include system messages, user
messages, assistant messages, and tool messages. Note: The input
must not consist of system messages or assistant messages only.
items:
oneOf:
- title: User Message
type: object
properties:
role:
type: string
enum:
- user
description: Role of the message author
default: user
content:
oneOf:
- type: string
description: Text message content
example: >-
What opportunities and challenges will the Chinese
large model industry face in 2025?
required:
- role
- content
- title: System Message
type: object
properties:
role:
type: string
enum:
- system
description: Role of the message author
default: system
content:
oneOf:
- type: string
description: Message text content
example: You are a helpful assistant.
required:
- role
- content
- title: Assistant Message
type: object
description: Can include tool calls
properties:
role:
type: string
enum:
- assistant
description: Role of the message author
default: assistant
content:
oneOf:
- type: string
description: Text message content
example: I'll help you with that analysis.
tool_calls:
type: array
description: >-
Tool call messages generated by the model. When this field
is provided, content is usually empty.
items:
type: object
properties:
id:
type: string
description: Tool call ID
type:
type: string
description: Tool type, supports web_search, retrieval, function
enum:
- function
- web_search
- retrieval
function:
type: object
description: >-
Function call information, not empty when type is
function
properties:
name:
type: string
description: Function name
arguments:
type: string
description: Function parameters, JSON format string
required:
- name
- arguments
required:
- id
- type
required:
- role
- title: Tool Message
type: object
properties:
role:
type: string
enum:
- tool
description: Role of the message author
default: tool
content:
oneOf:
- type: string
description: Message text content
example: 'Function executed successfully with result: ...'
tool_call_id:
type: string
description: Indicates the tool call ID corresponding to this message
required:
- role
- content
- tool_call_id
minItems: 1
do_sample:
type: boolean
example: true
default: true
description: >-
When do_sample is true, sampling strategy is enabled; when do_sample
is false, sampling strategy parameters such as temperature and top_p
will not take effect. Default value is `true`.
stream:
type: boolean
example: false
default: false
description: >-
This parameter should be set to false or omitted when using
synchronous call. It indicates that the model returns all content at
once after generating all content. Default value is false. If set to
true, the model will return the generated content in chunks via
standard Event Stream. When the Event Stream ends, a `data: [DONE]`
message will be returned.
thinking:
$ref: '#/components/schemas/ChatThinking'
temperature:
type: number
description: >-
Sampling temperature, controls the randomness of the output, must be
a positive number within the range: `[0.0, 1.0]`. The GLM-5.1,
GLM-5, GLM-4.7, GLM-4.6 series default value is `1.0`, GLM-4.5
series default value is `0.6`, GLM-4-32B-0414-128K default value is
`0.75`.
format: float
example: 1
default: 1
minimum: 0
maximum: 1
top_p:
type: number
description: >-
Another method of temperature sampling, value range is: `[0.01,
1.0]`. The GLM-5.1, GLM-5, GLM-4.7, GLM-4.6, GLM-4.5 series default
value is `0.95`, GLM-4-32B-0414-128K default value is `0.9`.
format: float
example: 0.95
default: 0.95
minimum: 0.01
maximum: 1
max_tokens:
type: integer
description: >-
The maximum number of tokens for model output, the GLM-5.1, GLM-5,
GLM-4.7, GLM-4.6 series supports 128K maximum output, the GLM-4.5
series supports 96K maximum output, the GLM-4.6v series supports 32K
maximum output, the GLM-4.5v series supports 16K maximum output,
GLM-4-32B-0414-128K supports 16K maximum output.
example: 1024
minimum: 1
maximum: 131072
tool_stream:
type: boolean
example: false
default: false
description: >-
Whether to enable streaming response for Function Calls. Default
value is false. Only supported by GLM-4.6 and above. Refer the
[Stream Tool Call](/guides/tools/stream-tool)
tools:
type: array
description: >
A list of tools the model may call. Currently, only functions are
supported as a tool. Use this to provide a list of functions the
model may generate JSON inputs for. A max of 128 functions are
supported.
items:
anyOf:
- $ref: '#/components/schemas/FunctionToolSchema'
- $ref: '#/components/schemas/RetrievalToolSchema'
- $ref: '#/components/schemas/WebSearchToolSchema'
tool_choice:
oneOf:
- type: string
enum:
- auto
description: >-
Used to control how the model selects which function to call.
This is only applicable when the tool type is function. The
default value is auto, and only auto is supported.
description: Controls how the model selects a tool.
stop:
type: array
description: >-
Stop word list. Generation stops when the model encounters any
specified string. Currently, only one stop word is supported, in the
format ["stop_word1"].
items:
type: string
maxItems: 4
response_format:
type: object
description: >-
Specifies the response format of the model. Defaults to text.
Supports two formats:{ "type": "text" } plain text mode, returns
natural language text, { "type": "json_object" } JSON mode, returns
valid JSON data. When using JSON mode, it’s recommended to clearly
request JSON output in the prompt.
properties:
type:
type: string
enum:
- text
- json_object
default: text
description: >-
Output format type: text for plain text, json_object for
JSON-formatted output.
required:
- type
request_id:
type: string
description: >-
Passed by the user side, needs to be unique; used to distinguish
each request, 6–64 characters. If not provided by the user side, the
platform will generate one by default.
minLength: 6
maxLength: 64
user_id:
type: string
description: >-
Unique ID for the end user, 6–128 characters. Avoid using sensitive
information.
minLength: 6
maxLength: 128
ChatCompletionVisionRequest:
required:
- model
- messages
type: object
properties:
model:
type: string
description: >-
The model code to be called. GLM-5V-Turbo are the new generation of
visual reasoning models. `AutoGLM-Phone-Multilingual` is mobile
intelligent assistant model.
example: glm-5v-turbo
default: glm-5v-turbo
enum:
- glm-5v-turbo
- glm-4.6v
- autoglm-phone-multilingual
- glm-4.6v-flash
- glm-4.6v-flashx
- glm-4.5v
messages:
type: array
description: >-
The current conversation message list as the model’s prompt input,
provided in JSON array format, e.g.,`{“role”: “user”, “content”:
“Hello”}`. Possible message types include system messages, user
messages. Note: The input must not consist of system or assistant
messages only.
items:
oneOf:
- title: User Message
type: object
properties:
role:
type: string
enum:
- user
description: Role of the message author
default: user
content:
oneOf:
- type: array
description: >-
Multimodal message content, supports text, images,
video, file
items:
$ref: '#/components/schemas/VisionMultimodalContentItem'
- type: string
description: >-
Text message content (can switch to multimodal message
above)
example: >-
What opportunities and challenges will the Chinese
large model industry face in 2025?
required:
- role
- content
- title: System Message
type: object
properties:
role:
type: string
enum:
- system
description: Role of the message author
default: system
content:
oneOf:
- type: string
description: Message text content
example: You are a helpful assistant.
required:
- role
- content
- title: Assistant Message
type: object
description: Can include tool calls
properties:
role:
type: string
enum:
- assistant
description: Role of the message author
default: assistant
content:
oneOf:
- type: string
description: Text message content
example: I'll help you with that analysis.
required:
- role
minItems: 1
do_sample:
type: boolean
example: true
default: true
description: >-
When do_sample is true, sampling strategy is enabled; when do_sample
is false, sampling strategy parameters such as temperature and top_p
will not take effect. Default value is `true`.
stream:
type: boolean
example: false
default: false
description: >-
This parameter should be set to false or omitted when using
synchronous call. It indicates that the model returns all content at
once after generating all content. Default value is false. If set to
true, the model will return the generated content in chunks via
standard Event Stream. When the Event Stream ends, a `data: [DONE]`
message will be returned.
thinking:
$ref: '#/components/schemas/ChatThinking'
temperature:
type: number
description: >-
Sampling temperature, controls the randomness of the output, must be
a positive number within the range: `[0.0, 1.0]`. The GLM-5V-Turbo,
GLM-4.6V, GLM-4.5V series default value is `0.8`, the
autoglm-phone-multilingual default value is `0.0`.
format: float
example: 0.8
default: 0.8
minimum: 0
maximum: 1
top_p:
type: number
description: >-
Another method of temperature sampling, value range is: `[0.01,
1.0]`, value range is: `[0.01, 1.0]`. The GLM-5V-Turbo, GLM-4.6V,
GLM-4.5V series default value is `0.6`, the
autoglm-phone-multilingual default value is `0.85`.
format: float
example: 0.6
default: 0.6
minimum: 0.01
maximum: 1
max_tokens:
type: integer
description: >-
The maximum number of tokens for model output, the GLM-5V-Turbo
supports 128K maximum output, GLM-4.6V series supports 32K maximum
output, the GLM-4.5V series supports 16K maximum output, the
autoglm-phone-multilingual supports 4K maximum output.
example: 1024
minimum: 1
maximum: 131072
tools:
type: array
description: >
A list of tools the model may call. Only support by GLM-4.6V series
and autoglm-phone-multilingual. Use this to provide a list of
functions the model may generate JSON inputs for. A max of 128
functions are supported.
items:
anyOf:
- $ref: '#/components/schemas/FunctionToolSchema'
tool_choice:
oneOf:
- type: string
enum:
- auto
description: >-
Used to control how the model selects which function to call.
This is only applicable when the tool type is function. The
default value is auto, and only auto is supported.
description: Controls how the model selects a tool.
stop:
type: array
description: >-
Stop word list. Generation stops when the model encounters any
specified string. Currently, only one stop word is supported, in the
format ["stop_word1"].
items:
type: string
maxItems: 4
request_id:
type: string
description: >-
Passed by the user side, needs to be unique; used to distinguish
each request, 6–64 characters. If not provided by the user side, the
platform will generate one by default.
minLength: 6
maxLength: 64
user_id:
type: string
description: >-
Unique ID for the end user, 6–128 characters. Avoid using sensitive
information.
minLength: 6
maxLength: 128
ChatCompletionResponse:
type: object
properties:
id:
type: string
description: Task ID
request_id:
description: Request ID
type: string
created:
description: Request creation time, Unix timestamp in seconds
type: integer
model:
description: Model name
type: string
choices:
type: array
description: List of model responses
items:
type: object
properties:
index:
type: integer
description: Result index.
message:
$ref: '#/components/schemas/ChatCompletionResponseMessage'
finish_reason:
type: string
description: >-
Reason for model inference termination. Can be `stop`,
`tool_calls`, `length`, `sensitive`,
`model_context_window_exceeded` or `network_error`.
usage:
type: object
description: Token usage statistics returned when the model call ends.
properties:
prompt_tokens:
type: number
description: Number of tokens in user input
completion_tokens:
type: number
description: Number of output tokens
prompt_tokens_details:
type: object
properties:
cached_tokens:
type: number
description: Number of tokens served from cache
total_tokens:
type: integer
description: Total number of tokens
web_search:
description: Search results.
type: array
items:
$ref: '#/components/schemas/WebSearchObjectResponse'
Error:
required:
- code
- message
type: object
description: The request has failed.
properties:
code:
type: integer
format: int32
description: Error code.
message:
type: string
description: Error message.
ChatThinking:
type: object
description: >-
Only supported by GLM-4.5 series and higher models. This parameter is
used to control whether the model enable the chain of thought.
properties:
type:
type: string
description: >-
Whether to enable the chain of thought(When enabled, GLM-5.1 GLM-5
GLM-5-Turbo GLM-5V-Turbo GLM-4.7 GLM-4.5V will think compulsorily,
while GLM-4.6, GLM-4.6V, GLM-4.5 and others will automatically
determine whether to think), default: enabled
default: enabled
enum:
- enabled
- disabled
clear_thinking:
type: boolean
description: >-
Default value is True. Controls whether to clear `reasoning_content`
from previous conversation turns. View more in [Thinking
Mode](/guides/capabilities/thinking-mode).
- `true` (default): For this request, the system ignores/removes `reasoning_content` from prior turns, and only keeps non-reasoning context (e.g., user/assistant visible text, tool calls, and tool results). This is recommended for general chat or lightweight tasks to reduce context length and cost.
- `false`: Retains `reasoning_content` from prior turns and includes it in the context sent to the model. To enable Preserved Thinking, you must forward the full, unmodified, and correctly ordered historical `reasoning_content` in `messages`. Missing, truncated, rewritten, or reordered blocks may degrade performance or prevent the feature from taking effect.
- Notes: This parameter only affects cross-turn historical thinking blocks; it does not change whether the model generates/returns thinking in the current turn.
default: true
example: true
FunctionToolSchema:
type: object
title: Function Call
properties:
type:
type: string
default: function
enum:
- function
function:
$ref: '#/components/schemas/FunctionObject'
required:
- type
- function
additionalProperties: false
RetrievalToolSchema:
type: object
title: Retrieval
properties:
type:
type: string
default: retrieval
enum:
- retrieval
retrieval:
$ref: '#/components/schemas/RetrievalObject'
required:
- type
- retrieval
additionalProperties: false
WebSearchToolSchema:
type: object
title: Web Search
properties:
type:
type: string
default: web_search
enum:
- web_search
web_search:
$ref: '#/components/schemas/WebSearchObject'
required:
- type
- web_search
additionalProperties: false
VisionMultimodalContentItem:
oneOf:
- title: Text
type: object
properties:
type:
type: string
enum:
- text
description: Content type is text
default: text
text:
type: string
description: Text content
required:
- type
- text
additionalProperties: false
- title: Image
type: object
properties:
type:
type: string
enum:
- image_url
description: Content type is image URL
default: image_url
image_url:
type: object
description: Image information
properties:
url:
type: string
description: >-
Image URL or Base64 encoding. Image size limit is under 5M
per image, with pixels not exceeding 6000*6000. GLM-5V
GLM4.6V series are limited to 150 sheets, GLM4.5V limit 50
sheets. Supports jpg, png, jpeg formats.
required:
- url
additionalProperties: false
required:
- type
- image_url
additionalProperties: false
- title: Video
type: object
properties:
type:
type: string
enum:
- video_url
description: Content type is video URL
default: video_url
video_url:
type: object
description: Video information.
properties:
url:
type: string
description: >-
Video URL address.The video size is limited to within 200
MB, GLM-5V GLM4.6V series are limited to 2 videos, GLM4.5V
limit 1 video, and the format supports `mp4`，`mkv`，`mov`.
required:
- url
additionalProperties: false
required:
- type
- video_url
additionalProperties: false
- title: File
type: object
properties:
type:
type: string
enum:
- file_url
description: >-
Content type is file URL, not support passing both the
`file_url` and `image_url` or `video_url` parameters at the same
time.
default: file_url
file_url:
type: object
description: File information.
properties:
url:
type: string
description: >-
File URL address. Only GLM-5V-Turbo, GLM-4.6V, GLM-4.5V
supported. Supports formats such as
pdf、txt、word、jsonl、xlsx、pptx, with a maximum of 50.
required:
- url
additionalProperties: false
required:
- type
- file_url
additionalProperties: false
ChatCompletionResponseMessage:
type: object
properties:
role:
type: string
description: Current conversation role, default is ‘assistant’ (model)
example: assistant
content:
type: string
description: >-
Current conversation content. Hits function is null, otherwise
returns model inference result.
For the GLM-4.5V series models, the output may contain the reasoning
process tags ` ` or the text boundary tags
`<|begin_of_box|> <|end_of_box|>`.
reasoning_content:
type: string
description: Reasoning content, supports by GLM-4.5 series.
tool_calls:
type: array
description: >-
Function names and parameters generated by the model that should be
called.
items:
$ref: '#/components/schemas/ChatCompletionResponseMessageToolCall'
WebSearchObjectResponse:
type: object
properties:
title:
type: string
description: Title.
content:
type: string
description: Content summary.
link:
type: string
description: Result URL.
media:
type: string
description: Website name.
icon:
type: string
description: Website icon.
refer:
type: string
description: Index number.
publish_date:
type: string
description: Website publication date.
FunctionObject:
type: object
properties:
name:
type: string
description: >-
The name of the function to be called. Must be a-z, A-Z, 0-9, or
contain underscores and dashes, with a maximum length of 64.
minLength: 1
maxLength: 64
pattern: ^[a-zA-Z0-9_-]+$
description:
type: string
description: >-
A description of what the function does, used by the model to choose
when and how to call the function.
parameters:
$ref: '#/components/schemas/FunctionParameters'
required:
- name
- description
- parameters
RetrievalObject:
type: object
properties:
knowledge_id:
type: string
description: Knowledge base ID, created or obtained from the platform
prompt_template:
type: string
description: >-
Prompt template for requesting the model, a custom request template
containing placeholders `{{ knowledge }}` and `{{ question }}`.
Default template: Search for the answer to the question
`{{question}}` in the document `{{ knowledge }}`. If an answer is
found, respond only using statements from the document; if no answer
is found, use your own knowledge to answer and inform the user that
the information is not from the document. Do not repeat the
question, start the answer directly.
required:
- knowledge_id
WebSearchObject:
type: object
properties:
enable:
type: boolean
description: |-
Whether to enable search functionality.
Default is `false`. Set to true to `enable`.
search_engine:
type: string
description: |-
Type of search engine.
Default is `search_pro_jina`. Supports: `search_pro_jina`.
enum:
- search_pro_jina
search_query:
type: string
description: Force trigger a search
count:
type: integer
description: |
Number of returned results
Range: `1-50`, max `50` results per search
Default is `10`
Supported engines: `search_pro_jina`
minimum: 1
maximum: 50
search_domain_filter:
type: string
description: >-
Limits search results to specified whitelisted domains. Whitelist:
input domains directly (e.g., www.example.com)
Supported engines: `search_pro_jina`
search_recency_filter:
type: string
description: |-
Limits search to a specific time range.
Default is `noLimit`
Values:
`oneDay`, within a day
`oneWeek`, within a week
`oneMonth`, within a month
`oneYear`, within a year
`noLimit`, no limit (default)
Supported engines: `search_pro_jina`
enum:
- oneDay
- oneWeek
- oneMonth
- oneYear
- noLimit
content_size:
type: string
description: >-
Number of characters for webpage summaries.
Default is `medium`
`medium`: Balanced mode for most queries. 400-600 characters
`high`: Maximizes context for comprehensive answers, 2500
characters.
enum:
- medium
- high
result_sequence:
type: string
description: >-
Specifies whether search results are shown before or after model
response. Options: `before`, `after`. Default is `after`
enum:
- before
- after
search_result:
type: boolean
description: |-
Whether to return search results in the response.
Default is `false`
require_search:
type: boolean
description: |-
Whether to force model response based on search result.
Default is `false`
search_prompt:
type: string
description: >-
Prompt to customize how search results are processed.
Default Prompt:
`You are an intelligent Q&A expert with the ability to synthesize
information, recognize time, understand semantics, and clean
contradictory data. The current date is {{current_date}}. Use this
as the only time reference. Based on the following information,
provide a comprehensive and accurate answer to the user's
question.Only extract valuable content for the answer. Ensure the
answer is timely and authoritative. State the answer directly
without citing data sources or internal processes.`
required:
- search_engine
ChatCompletionResponseMessageToolCall:
type: object
properties:
function:
type: object
description: >-
Contains the function name and JSON format parameters generated by
the model.
properties:
name:
type: string
description: Model-generated function name.
arguments:
type: object
description: >-
JSON format of the function call parameters generated by the
model. Validate the parameters before calling the function.
required:
- name
- arguments
id:
type: string
description: Unique identifier for the hit function.
type:
type: string
description: Tool type called by the model, currently only supports ‘function’.
FunctionParameters:
type: object
description: >-
Parameters defined using JSON Schema. Must pass a JSON Schema object to
accurately define accepted parameters. Omit if no parameters are needed
when calling the function.
additionalProperties: true
securitySchemes:
bearerAuth:
type: http
scheme: bearer
description: >-
Use the following format for authentication: Bearer [](https://z.ai/manage-apikey/apikey-list)
````