Streaming events

StreamEvent module-attribute

StreamEvent: TypeAlias = Union[
    RawResponsesStreamEvent,
    RunItemStreamEvent,
    AgentUpdatedStreamEvent,
]

A streaming event from an agent.

RawResponsesStreamEvent dataclass

Streaming event from the LLM. These are 'raw' events, i.e. they are directly passed through from the LLM.

Source code in src/agents/stream_events.py

@dataclass
class RawResponsesStreamEvent:
    """Streaming event from the LLM. These are 'raw' events, i.e. they are directly passed through
    from the LLM.
    """

    data: TResponseStreamEvent
    """The raw responses streaming event from the LLM."""

    type: Literal["raw_response_event"] = "raw_response_event"
    """The type of the event."""

data instance-attribute

data: TResponseStreamEvent

The raw responses streaming event from the LLM.

type class-attribute instance-attribute

type: Literal['raw_response_event'] = 'raw_response_event'

The type of the event.

RunItemStreamEvent dataclass

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.

Source code in src/agents/stream_events.py

@dataclass
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_search_called",
        "tool_search_output_created",
        "tool_output",
        "reasoning_item_created",
        "mcp_approval_requested",
        "mcp_approval_response",
        "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"

name instance-attribute

name: Literal[
    "message_output_created",
    "handoff_requested",
    "handoff_occured",
    "tool_called",
    "tool_search_called",
    "tool_search_output_created",
    "tool_output",
    "reasoning_item_created",
    "mcp_approval_requested",
    "mcp_approval_response",
    "mcp_list_tools",
]

The name of the event.

item instance-attribute

item: RunItem

The item that was created.

AgentUpdatedStreamEvent dataclass

Event that notifies that there is a new agent running.

Source code in src/agents/stream_events.py

@dataclass
class AgentUpdatedStreamEvent:
    """Event that notifies that there is a new agent running."""

    new_agent: Agent[Any]
    """The new agent."""

    type: Literal["agent_updated_stream_event"] = "agent_updated_stream_event"

new_agent instance-attribute

new_agent: Agent[Any]

The new agent.