id of the last ChatMessage present when this tool call was
inserted (-1 when there were none). The tool call renders immediately
after that message; if the anchor message has slid out of the retained
window, the tool call renders before all messages.
The tool's arguments, as the model sent them.
Values are DefaultToolResult — any — for the same reason a tool
result is: the shape is the author's own Zod schema, which the framework
cannot see from here. As Record<string, unknown> the ordinary
toolCall.args.url was a compile error in a client that runs correctly,
and the escape hatch agents reached for next (args as FetchJsonArgs) is
itself an error — TypeScript rejects the cast as insufficiently
overlapping. That pair cost two build rounds in one run.
Annotate at the read site for real checking:
const { url } = toolCall.args as { url: string } is still available, and
now actually compiles.
OptionalresultMonotonically increasing, session-unique insertion sequence number.
Tool calls in a snapshot are always sorted ascending by seq.
Info about a tool call for display in the UI.