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JavaScript@langchain/coremessagestoolToolCallChunk
Interfaceā—Since v1.0

ToolCallChunk

Copy
interface ToolCallChunk

Properties

View source on GitHub

Example

property
args: string
property
id: string
property
index: number
property
name: TName
property
type: "tool_call_chunk"

A chunk of a tool call (e.g., as part of a stream). When merging ToolCallChunks (e.g., via AIMessageChunk.add), all string attributes are concatenated. Chunks are only merged if their values of index are equal and not None.

Copy
const leftChunks = [
  {
    name: "foo",
    args: '{"a":',
    index: 0
  }
];

const leftAIMessageChunk = new AIMessageChunk({
  content: "",
  tool_call_chunks: leftChunks
});

const rightChunks = [
  {
    name: undefined,
    args: '1}',
    index: 0
  }
];

const rightAIMessageChunk = new AIMessageChunk({
  content: "",
  tool_call_chunks: rightChunks
});

const result = leftAIMessageChunk.concat(rightAIMessageChunk);
// result.tool_call_chunks is equal to:
// [
//   {
//     name: "foo",
//     args: '{"a":1}'
//     index: 0
//   }
// ]