Interface: ToolCallStartEvent#

Defined in: packages/ai/src/types.ts:1057

Emitted when a tool call starts.

@ag-ui/core provides: toolCallId, toolCallName, parentMessageId? TanStack AI adds: model?, toolName (deprecated alias), index?, metadata?

Extends#

• ToolCallStartEvent

Indexable#

[k: string]: unknown

Properties#

index?#

optional index: number;

Defined in: packages/ai/src/types.ts:1066

Index for parallel tool calls

metadata?#

optional metadata: Record<string, unknown>;

Defined in: packages/ai/src/types.ts:1071

Provider-specific metadata to carry into the ToolCall. Untyped at the event layer because events flow through a discriminated union that does not survive generics; adapters cast it to their typed TToolCallMetadata shape when emitting.

model?#

optional model: string;

Defined in: packages/ai/src/types.ts:1059

Model identifier for multi-model support

toolName#

toolName: string;

Defined in: packages/ai/src/types.ts:1064

Deprecated#

Use toolCallName instead (from @ag-ui/core spec). Kept for backward compatibility.