Class●Since v0.3

BaseMessage

Base class for all types of messages in a conversation. It includes properties like content, name, and additional_kwargs. It also includes methods like toDict() and _getType().

class BaseMessage

Bases

Serializable

Constructors

constructor

constructor→ BaseMessage<TStructure, TRole>

Properties

property

additional_kwargs: __type

property

content: $InferMessageContent<TStructure, TRole>

Array of content blocks that make up the message content

property

id: string

Unique identifier for this message

property

lc_kwargs: SerializedFields

property

lc_namespace: string[]

A path to the module that contains the class, eg. ["langchain", "llms"] Usually should be the same as the entrypoint the class is exported from.

property

lc_serializable: boolean

property

name: string

An optional name for the message participant.

This property is primarily used to:

Identify agent roles in multi-agent systems: When multiple agents collaborate, setting name helps distinguish which agent produced a message, preventing confusion about who said what.
Pass participant names to model providers: Some providers (notably OpenAI, e.g. see OpenAI Chat Completions API) use this field to differentiate between participants with the same role. For example, when using OpenAI's Chat Completions API, the name is included in the message payload sent to the model.

// Setting name on an AIMessage to identify the agent
const message = new AIMessage({
  content: "I'll handle the calendar scheduling.",
  name: "calendar_agent"
});

// In a multi-agent system, this helps track message origins
const researcherMessage = new AIMessage({
  content: "Here are the findings...",
  name: "researcher"
});
const writerMessage = new AIMessage({
  content: "I've drafted the report.",
  name: "writer"
});