class RunItemStreamEvent: """Streaming events that wrap a `RunItem`. As the agent processes the LLM response, it will  generate these events for new messages, tool calls, tool outputs, handoffs, etc.  """ name: Literal[ "message_output_created", "handoff_requested", # This is misspelled, but we can't change it because that would be a breaking change "handoff_occured", "tool_called", "tool_output", "reasoning_item_created", "mcp_approval_requested", "mcp_list_tools", ] """The name of the event.""" item: RunItem """The item that was created.""" type: Literal["run_item_stream_event"] = "run_item_stream_event" vs RunItem: TypeAlias = Union[ MessageOutputItem, HandoffCallItem, HandoffOutputItem, ToolCallItem, ToolCallOutputItem, ReasoningItem, MCPListToolsItem, MCPApprovalRequestItem, MCPApprovalResponseItem, ] """An item generated by an agent."""