Assistants API (Preview) messages reference

Note

• File search can ingest up to 10,000 files per assistant - 500 times more than before. It is fast, supports parallel queries through multi-threaded searches, and features enhanced reranking and query rewriting.
  • Vector store is a new object in the API. Once a file is added to a vector store, it's automatically parsed, chunked, and embedded, made ready to be searched. Vector stores can be used across assistants and threads, simplifying file management and billing.
• We've added support for the tool_choice parameter which can be used to force the use of a specific tool (like file search, code interpreter, or a function) in a particular run.

This article provides reference documentation for Python and REST for the new Assistants API (Preview). More in-depth step-by-step guidance is provided in the getting started guide.

Create message

POST https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages?api-version=2024-08-01-preview

Create a message.

Path parameter

Parameter	Type	Required	Description
thread_id	string	Required	The ID of the thread to create a message for.

Request body

Name	Type	Required	Description
role	string	Required	The role of the entity that is creating the message. Can be user or assistant. user indicates the message is sent by an actual user and should be used in most cases to represent user-generated messages. assistant indicates the message is generated by the assistant. Use this value to insert messages from the assistant into the conversation.
content	string	Required	The content of the message.
attachments	array	Optional	A list of files attached to the message, and the tools they should be added to.
metadata	map	Optional	Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format. Keys can be a maximum of 64 characters long and values can be a maximum of 512 characters long.

Returns

A message object.

Example create message request

Python 1.x

from openai import AzureOpenAI
    
client = AzureOpenAI(
    api_key=os.getenv("AZURE_OPENAI_API_KEY"),  
    api_version="2024-08-01-preview",
    azure_endpoint = os.getenv("AZURE_OPENAI_ENDPOINT")
    )

thread_message = client.beta.threads.messages.create(
  "thread_abc123",
  role="user",
  content="How does AI work? Explain it in simple terms.",
)
print(thread_message)

REST

curl https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages?api-version=2024-08-01-preview \
  -H "api-key: $AZURE_OPENAI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
      "role": "user",
      "content": "How does AI work? Explain it in simple terms."
    }' 

List messages

GET https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages?api-version=2024-08-01-preview

Returns a list of messages for a given thread.

Path Parameters

Parameter	Type	Required	Description
thread_id	string	Required	The ID of the thread that messages belong to.

Query Parameters

Name	Type	Required	Description
limit	integer	Optional - Defaults to 20	A limit on the number of objects to be returned. Limit can range between 1 and 100, and the default is 20.
order	string	Optional - Defaults to desc	Sort order by the created_at timestamp of the objects. asc for ascending order and desc for descending order.
after	string	Optional	A cursor for use in pagination. after is an object ID that defines your place in the list. For instance, if you make a list request and receive 100 objects, ending with obj_foo, your subsequent call can include after=obj_foo in order to fetch the next page of the list.
run_id	string	Optionanl	Filter messages by the run ID that generated them.
before	string	Optional	A cursor for use in pagination. before is an object ID that defines your place in the list. For instance, if you make a list request and receive 100 objects, ending with obj_foo, your subsequent call can include before=obj_foo in order to fetch the previous page of the list.

Returns

A list of message objects.

Example list messages request

Python 1.x

from openai import AzureOpenAI
    
client = AzureOpenAI(
    api_key=os.getenv("AZURE_OPENAI_API_KEY"),  
    api_version="2024-08-01-preview",
    azure_endpoint = os.getenv("AZURE_OPENAI_ENDPOINT")
    )

thread_messages = client.beta.threads.messages.list("thread_abc123")
print(thread_messages.data)

REST

curl https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages?api-version=2024-08-01-preview \
  -H "api-key: $AZURE_OPENAI_API_KEY" \
  -H 'Content-Type: application/json' 

Retrieve message

GET https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages/{message_id}?api-version=2024-08-01-preview

Retrieves a message file.

Path parameters

Parameter	Type	Required	Description
thread_id	string	Required	The ID of the thread that the message belongs to.
message_id	string	Required	The ID of the message to retrieve.

Returns

The message object matching the specified ID.

Example retrieve message request

Python 1.x

from openai import AzureOpenAI

client = AzureOpenAI(
    api_key=os.getenv("AZURE_OPENAI_API_KEY"),  
    api_version="2024-05-01-preview",
    azure_endpoint = os.getenv("AZURE_OPENAI_ENDPOINT")
    )

message = client.beta.threads.messages.retrieve(
  message_id="msg_abc123",
  thread_id="thread_abc123",
)
print(message)

REST

curl https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages/{message_id}?api-version=2024-08-01-preview \
  -H "api-key: $AZURE_OPENAI_API_KEY" \
  -H 'Content-Type: application/json' 

Modify message

POST https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages/{message_id}?api-version=2024-08-01-preview

Modifies a message.

Path parameters

Parameter	Type	Required	Description
thread_id	string	Required	The ID of the thread to which the message belongs.
message_id	string	Required	The ID of the message to modify.

Request body

Parameter	Type	Required	Description
metadata	map	Optional	Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format. Keys can be a maximum of 64 characters long and values can be a maximum of 512 characters long.

Returns

The modified message object.

Python 1.x

from openai import AzureOpenAI
    
client = AzureOpenAI(
    api_key=os.getenv("AZURE_OPENAI_API_KEY"),  
    api_version="2024-08-01-preview",
    azure_endpoint = os.getenv("AZURE_OPENAI_ENDPOINT")
    )

message = client.beta.threads.messages.update(
  message_id="msg_abc12",
  thread_id="thread_abc123",
  metadata={
    "modified": "true",
    "user": "abc123",
  },
)
print(message)

REST

curl https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages/{message_id}?api-version=2024-08-01-preview
``` \
  -H "api-key: $AZURE_OPENAI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
      "metadata": {
        "modified": "true",
        "user": "abc123"
      }
    }'  
   

Delete message

DELETE https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages/{message_id}?api-version=2024-08-01-preview

Deletes a message.

Path parameters

Parameter	Type	Required	Description
thread_id	string	Required	The ID of the thread to which the message belongs.
message_id	string	Required	The ID of the message to modify.

Returns

The deletion status of the message object.

Python 1.x

from openai import AzureOpenAI
client = AzureOpenAI(
    api_key=os.getenv("AZURE_OPENAI_API_KEY"),  
    api_version="2024-08-01-preview",
    azure_endpoint = os.getenv("AZURE_OPENAI_ENDPOINT")
    )

deleted_message = client.beta.threads.messages.delete(
  message_id="msg_abc12",
  thread_id="thread_abc123",
)
print(deleted_message)

REST

curl -x DELETE https://YOUR_RESOURCE_NAME.openai.azure.com/openai/threads/{thread_id}/messages/{message_id}?api-version=2024-08-01-preview \
  -H "api-key: $AZURE_OPENAI_API_KEY" \
  -H 'Content-Type: application/json'

Message object

Represents a message within a thread.

Name	Type	Description
id	string	The identifier, which can be referenced in API endpoints.
object	string	The object type, which is always thread.message.
created_at	integer	The Unix timestamp (in seconds) for when the message was created.
thread_id	string	The thread ID that this message belongs to.
role	string	The entity that produced the message. One of user or assistant.
content	array	The content of the message in array of text and/or images.
assistant_id	string or null	If applicable, the ID of the assistant that authored this message.
run_id	string or null	If applicable, the ID of the run associated with the authoring of this message.
file_ids	array	A list of file IDs that the assistant should use. Useful for tools like retrieval and code_interpreter that can access files. A maximum of 10 files can be attached to a message.
metadata	map	Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format. Keys can be a maximum of 64 characters long and values can be a maximum of 512 characters long.