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JavaScript@langchain/coremessagesMessageType

Type●Since v0.3

MessageType

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MessageType: "ai" | "human" | "tool" | "system" | string  NonNullable<unknown>

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Example

Represents the possible types of messages in the system. Includes standard message types ("ai", "human", "tool", "system") and allows for custom string types that are non-null.

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// Standard message types
const messageType1: MessageType = "ai";
const messageType2: MessageType = "human";

// Custom message type
const messageType3: MessageType = "custom_type";