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Language

Theme

JavaScript@langchain/coremessagesContentBlockToolsToolCall

Interface●Since v1.0

ToolCall

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interface ToolCall

Bases

BaseContentBlock

Used in Docs

Quickstart
Use the functional API
Workflows and agents

Properties

View source on GitHub

Example

property

args: TArgs

property

id: string

property

name: TName

property

type: "tool_call"

Represents a request to call a tool.

The arguments to the tool call

Content block identifier, which can be either

generated by the provider (e.g., a provider-specific ID)
generated by LangChain upon creation (a uuid prefixed with 'lc-')

The name of the tool being called

Type of the content block

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const toolCall: ToolCall = {
    type: "tool_call",
    name: "foo",
    args: { a: 1 },
    callId: "123"
};