Tool call ID
Tool name
OptionallabelTool label for display
Human-readable description of what the tool is doing
Current execution status
OptionalargsArguments passed to the tool
OptionalresultResult summary (for display)
OptionalerrorError message if failed
OptionalstartedTimestamp when started
OptionalendedTimestamp when completed/failed
OptionaldownloadDownloadable file information
Tool execution item for chat display Used by frontend to render tool calls with status indicators