BaseMessageChunk

class langchain_core.messages.base.BaseMessageChunk

Bases: BaseMessage

Message chunk, which can be concatenated with other Message chunks.

Pass in content as positional arg.

Parameters:

• content – The string contents of the message.

• kwargs – Additional fields to pass to the

param additional_kwargs: dict [Optional]

Reserved for additional payload data associated with the message.

For example, for a message from an AI, this could include tool calls as encoded by the model provider.

param content: str | list[str | dict] [Required]

The string contents of the message.

param id: str | None = None

An optional unique identifier for the message. This should ideally be provided by the provider/model which created the message.

param name: str | None = None

An optional name for the message.

This can be used to provide a human-readable name for the message.

Usage of this field is optional, and whether it’s used or not is up to the model implementation.

param response_metadata: dict [Optional]

Response metadata. For example: response headers, logprobs, token counts.

param type: str [Required]

The type of the message. Must be a string that is unique to the message type.

The purpose of this field is to allow for easy identification of the message type when deserializing messages.

pretty_print() → None

Return type:

None

pretty_repr(html: bool = False) → str

Get a pretty representation of the message.

Parameters:

html (bool) – Whether to format the message as HTML. If True, the message will be formatted with HTML tags. Default is False.

Returns:

A pretty representation of the message.

Return type:

str