The argument fragment to append
The tool call ID this delta belongs to
OptionalasOptionalasRepresents the content as a string. Returns undefined if the content
is purely informational and/or visual and should not be included in the overall
representation of the response.
OptionalmergeOptionaltoOptionalto
Represents a streaming delta update for tool call arguments. This content type is used during streaming to append argument fragments to an existing ToolCallChatResponseContent rather than replacing the full arguments.