feat: add additional a2a events and enrich event metadata

lib/crewai/src/crewai/a2a/task_helpers.py

@@ -3,9 +3,10 @@
 from __future__ import annotations
 
 from collections.abc import AsyncIterator
-from typing import TYPE_CHECKING, TypedDict
+from typing import TYPE_CHECKING, Any, TypedDict
 import uuid
 
+from a2a.client.errors import A2AClientHTTPError
 from a2a.types import (
     AgentCard,
     Message,
@@ -20,7 +21,10 @@ from a2a.types import (
 from typing_extensions import NotRequired
 
 from crewai.events.event_bus import crewai_event_bus
-from crewai.events.types.a2a_events import A2AResponseReceivedEvent
+from crewai.events.types.a2a_events import (
+    A2AConnectionErrorEvent,
+    A2AResponseReceivedEvent,
+)
 
 
 if TYPE_CHECKING:
@@ -55,7 +59,8 @@ class TaskStateResult(TypedDict):
     history: list[Message]
     result: NotRequired[str]
     error: NotRequired[str]
-    agent_card: NotRequired[AgentCard]
+    agent_card: NotRequired[dict[str, Any]]
+    a2a_agent_name: NotRequired[str | None]
 
 
 def extract_task_result_parts(a2a_task: A2ATask) -> list[str]:
@@ -131,50 +136,69 @@ def process_task_state(
     is_multiturn: bool,
     agent_role: str | None,
     result_parts: list[str] | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    is_final: bool = True,
 ) -> TaskStateResult | None:
     """Process A2A task state and return result dictionary.
 
     Shared logic for both polling and streaming handlers.
 
     Args:
-        a2a_task: The A2A task to process
+        a2a_task: The A2A task to process.
-        new_messages: List to collect messages (modified in place)
+        new_messages: List to collect messages (modified in place).
-        agent_card: The agent card
+        agent_card: The agent card.
-        turn_number: Current turn number
+        turn_number: Current turn number.
-        is_multiturn: Whether multi-turn conversation
+        is_multiturn: Whether multi-turn conversation.
-        agent_role: Agent role for logging
+        agent_role: Agent role for logging.
         result_parts: Accumulated result parts (streaming passes accumulated,
-            polling passes None to extract from task)
+            polling passes None to extract from task).
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        from_task: Optional CrewAI Task for event metadata.
+        from_agent: Optional CrewAI Agent for event metadata.
+        is_final: Whether this is the final response in the stream.
 
     Returns:
-        Result dictionary if terminal/actionable state, None otherwise
+        Result dictionary if terminal/actionable state, None otherwise.
     """
-    should_extract = result_parts is None
     if result_parts is None:
         result_parts = []
 
     if a2a_task.status.state == TaskState.completed:
-        if should_extract:
+        if not result_parts:
             extracted_parts = extract_task_result_parts(a2a_task)
             result_parts.extend(extracted_parts)
         if a2a_task.history:
             new_messages.extend(a2a_task.history)
 
         response_text = " ".join(result_parts) if result_parts else ""
+        message_id = None
+        if a2a_task.status and a2a_task.status.message:
+            message_id = a2a_task.status.message.message_id
         crewai_event_bus.emit(
             None,
             A2AResponseReceivedEvent(
                 response=response_text,
                 turn_number=turn_number,
+                context_id=a2a_task.context_id,
+                message_id=message_id,
                 is_multiturn=is_multiturn,
                 status="completed",
+                final=is_final,
                 agent_role=agent_role,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
             ),
         )
 
         return TaskStateResult(
             status=TaskState.completed,
-            agent_card=agent_card,
+            agent_card=agent_card.model_dump(exclude_none=True),
             result=response_text,
             history=new_messages,
         )
@@ -194,14 +218,24 @@ def process_task_state(
             )
             new_messages.append(agent_message)
 
+        input_message_id = None
+        if a2a_task.status and a2a_task.status.message:
+            input_message_id = a2a_task.status.message.message_id
         crewai_event_bus.emit(
             None,
             A2AResponseReceivedEvent(
                 response=response_text,
                 turn_number=turn_number,
+                context_id=a2a_task.context_id,
+                message_id=input_message_id,
                 is_multiturn=is_multiturn,
                 status="input_required",
+                final=is_final,
                 agent_role=agent_role,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
             ),
         )
 
@@ -209,7 +243,7 @@ def process_task_state(
             status=TaskState.input_required,
             error=response_text,
             history=new_messages,
-            agent_card=agent_card,
+            agent_card=agent_card.model_dump(exclude_none=True),
         )
 
     if a2a_task.status.state in {TaskState.failed, TaskState.rejected}:
@@ -248,6 +282,11 @@ async def send_message_and_get_task_id(
     turn_number: int,
     is_multiturn: bool,
     agent_role: str | None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    context_id: str | None = None,
 ) -> str | TaskStateResult:
     """Send message and process initial response.
 
@@ -262,6 +301,11 @@ async def send_message_and_get_task_id(
         turn_number: Current turn number
         is_multiturn: Whether multi-turn conversation
         agent_role: Agent role for logging
+        from_task: Optional CrewAI Task object for event metadata.
+        from_agent: Optional CrewAI Agent object for event metadata.
+        endpoint: Optional A2A endpoint URL.
+        a2a_agent_name: Optional A2A agent name.
+        context_id: Optional A2A context ID for correlation.
 
     Returns:
         Task ID string if agent needs polling/waiting, or TaskStateResult if done.
@@ -280,9 +324,16 @@ async def send_message_and_get_task_id(
                     A2AResponseReceivedEvent(
                         response=response_text,
                         turn_number=turn_number,
+                        context_id=event.context_id,
+                        message_id=event.message_id,
                         is_multiturn=is_multiturn,
                         status="completed",
+                        final=True,
                         agent_role=agent_role,
+                        endpoint=endpoint,
+                        a2a_agent_name=a2a_agent_name,
+                        from_task=from_task,
+                        from_agent=from_agent,
                     ),
                 )
 
@@ -290,7 +341,7 @@ async def send_message_and_get_task_id(
                     status=TaskState.completed,
                     result=response_text,
                     history=new_messages,
-                    agent_card=agent_card,
+                    agent_card=agent_card.model_dump(exclude_none=True),
                 )
 
             if isinstance(event, tuple):
@@ -304,6 +355,10 @@ async def send_message_and_get_task_id(
                         turn_number=turn_number,
                         is_multiturn=is_multiturn,
                         agent_role=agent_role,
+                        endpoint=endpoint,
+                        a2a_agent_name=a2a_agent_name,
+                        from_task=from_task,
+                        from_agent=from_agent,
                     )
                     if result:
                         return result
@@ -316,6 +371,99 @@ async def send_message_and_get_task_id(
             history=new_messages,
         )
 
+    except A2AClientHTTPError as e:
+        error_msg = f"HTTP Error {e.status_code}: {e!s}"
+
+        error_message = Message(
+            role=Role.agent,
+            message_id=str(uuid.uuid4()),
+            parts=[Part(root=TextPart(text=error_msg))],
+            context_id=context_id,
+        )
+        new_messages.append(error_message)
+
+        crewai_event_bus.emit(
+            None,
+            A2AConnectionErrorEvent(
+                endpoint=endpoint or "",
+                error=str(e),
+                error_type="http_error",
+                status_code=e.status_code,
+                a2a_agent_name=a2a_agent_name,
+                operation="send_message",
+                context_id=context_id,
+                from_task=from_task,
+                from_agent=from_agent,
+            ),
+        )
+        crewai_event_bus.emit(
+            None,
+            A2AResponseReceivedEvent(
+                response=error_msg,
+                turn_number=turn_number,
+                context_id=context_id,
+                is_multiturn=is_multiturn,
+                status="failed",
+                final=True,
+                agent_role=agent_role,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
+            ),
+        )
+        return TaskStateResult(
+            status=TaskState.failed,
+            error=error_msg,
+            history=new_messages,
+        )
+
+    except Exception as e:
+        error_msg = f"Unexpected error during send_message: {e!s}"
+
+        error_message = Message(
+            role=Role.agent,
+            message_id=str(uuid.uuid4()),
+            parts=[Part(root=TextPart(text=error_msg))],
+            context_id=context_id,
+        )
+        new_messages.append(error_message)
+
+        crewai_event_bus.emit(
+            None,
+            A2AConnectionErrorEvent(
+                endpoint=endpoint or "",
+                error=str(e),
+                error_type="unexpected_error",
+                a2a_agent_name=a2a_agent_name,
+                operation="send_message",
+                context_id=context_id,
+                from_task=from_task,
+                from_agent=from_agent,
+            ),
+        )
+        crewai_event_bus.emit(
+            None,
+            A2AResponseReceivedEvent(
+                response=error_msg,
+                turn_number=turn_number,
+                context_id=context_id,
+                is_multiturn=is_multiturn,
+                status="failed",
+                final=True,
+                agent_role=agent_role,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
+            ),
+        )
+        return TaskStateResult(
+            status=TaskState.failed,
+            error=error_msg,
+            history=new_messages,
+        )
+
     finally:
         aclose = getattr(event_stream, "aclose", None)
         if aclose:

lib/crewai/src/crewai/a2a/updates/base.py

@@ -22,6 +22,13 @@ class BaseHandlerKwargs(TypedDict, total=False):
     turn_number: int
     is_multiturn: bool
     agent_role: str | None
+    context_id: str | None
+    task_id: str | None
+    endpoint: str | None
+    agent_branch: Any
+    a2a_agent_name: str | None
+    from_task: Any
+    from_agent: Any
 
 
 class PollingHandlerKwargs(BaseHandlerKwargs, total=False):
@@ -29,8 +36,6 @@ class PollingHandlerKwargs(BaseHandlerKwargs, total=False):
 
     polling_interval: float
     polling_timeout: float
-    endpoint: str
-    agent_branch: Any
     history_length: int
     max_polls: int | None
 
@@ -38,9 +43,6 @@ class PollingHandlerKwargs(BaseHandlerKwargs, total=False):
 class StreamingHandlerKwargs(BaseHandlerKwargs, total=False):
     """Kwargs for streaming handler."""
 
-    context_id: str | None
-    task_id: str | None
-
 
 class PushNotificationHandlerKwargs(BaseHandlerKwargs, total=False):
     """Kwargs for push notification handler."""
@@ -49,7 +51,6 @@ class PushNotificationHandlerKwargs(BaseHandlerKwargs, total=False):
     result_store: PushNotificationResultStore
     polling_timeout: float
     polling_interval: float
-    agent_branch: Any
 
 
 class PushNotificationResultStore(Protocol):

lib/crewai/src/crewai/a2a/updates/polling/handler.py

@@ -31,6 +31,7 @@ from crewai.a2a.task_helpers import (
 from crewai.a2a.updates.base import PollingHandlerKwargs
 from crewai.events.event_bus import crewai_event_bus
 from crewai.events.types.a2a_events import (
+    A2AConnectionErrorEvent,
     A2APollingStartedEvent,
     A2APollingStatusEvent,
     A2AResponseReceivedEvent,
@@ -49,23 +50,33 @@ async def _poll_task_until_complete(
     agent_branch: Any | None = None,
     history_length: int = 100,
     max_polls: int | None = None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    context_id: str | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
 ) -> A2ATask:
     """Poll task status until terminal state reached.
 
     Args:
-        client: A2A client instance
+        client: A2A client instance.
-        task_id: Task ID to poll
+        task_id: Task ID to poll.
-        polling_interval: Seconds between poll attempts
+        polling_interval: Seconds between poll attempts.
-        polling_timeout: Max seconds before timeout
+        polling_timeout: Max seconds before timeout.
-        agent_branch: Agent tree branch for logging
+        agent_branch: Agent tree branch for logging.
-        history_length: Number of messages to retrieve per poll
+        history_length: Number of messages to retrieve per poll.
-        max_polls: Max number of poll attempts (None = unlimited)
+        max_polls: Max number of poll attempts (None = unlimited).
+        from_task: Optional CrewAI Task object for event metadata.
+        from_agent: Optional CrewAI Agent object for event metadata.
+        context_id: A2A context ID for correlation.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
 
     Returns:
-        Final task object in terminal state
+        Final task object in terminal state.
 
     Raises:
-        A2APollingTimeoutError: If polling exceeds timeout or max_polls
+        A2APollingTimeoutError: If polling exceeds timeout or max_polls.
     """
     start_time = time.monotonic()
     poll_count = 0
@@ -77,13 +88,19 @@ async def _poll_task_until_complete(
         )
 
         elapsed = time.monotonic() - start_time
+        effective_context_id = task.context_id or context_id
         crewai_event_bus.emit(
             agent_branch,
             A2APollingStatusEvent(
                 task_id=task_id,
+                context_id=effective_context_id,
                 state=str(task.status.state.value) if task.status.state else "unknown",
                 elapsed_seconds=elapsed,
                 poll_count=poll_count,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
             ),
         )
 
@@ -137,6 +154,9 @@ class PollingHandler:
         max_polls = kwargs.get("max_polls")
         context_id = kwargs.get("context_id")
         task_id = kwargs.get("task_id")
+        a2a_agent_name = kwargs.get("a2a_agent_name")
+        from_task = kwargs.get("from_task")
+        from_agent = kwargs.get("from_agent")
 
         try:
             result_or_task_id = await send_message_and_get_task_id(
@@ -146,6 +166,11 @@ class PollingHandler:
                 turn_number=turn_number,
                 is_multiturn=is_multiturn,
                 agent_role=agent_role,
+                from_task=from_task,
+                from_agent=from_agent,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                context_id=context_id,
             )
 
             if not isinstance(result_or_task_id, str):
@@ -157,8 +182,12 @@ class PollingHandler:
                 agent_branch,
                 A2APollingStartedEvent(
                     task_id=task_id,
+                    context_id=context_id,
                     polling_interval=polling_interval,
                     endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
                 ),
             )
 
@@ -170,6 +199,11 @@ class PollingHandler:
                 agent_branch=agent_branch,
                 history_length=history_length,
                 max_polls=max_polls,
+                from_task=from_task,
+                from_agent=from_agent,
+                context_id=context_id,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
             )
 
             result = process_task_state(
@@ -179,6 +213,10 @@ class PollingHandler:
                 turn_number=turn_number,
                 is_multiturn=is_multiturn,
                 agent_role=agent_role,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
             )
             if result:
                 return result
@@ -206,9 +244,15 @@ class PollingHandler:
                 A2AResponseReceivedEvent(
                     response=error_msg,
                     turn_number=turn_number,
+                    context_id=context_id,
                     is_multiturn=is_multiturn,
                     status="failed",
+                    final=True,
                     agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
                 ),
             )
             return TaskStateResult(
@@ -229,14 +273,83 @@ class PollingHandler:
             )
             new_messages.append(error_message)
 
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint,
+                    error=str(e),
+                    error_type="http_error",
+                    status_code=e.status_code,
+                    a2a_agent_name=a2a_agent_name,
+                    operation="polling",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
             crewai_event_bus.emit(
                 agent_branch,
                 A2AResponseReceivedEvent(
                     response=error_msg,
                     turn_number=turn_number,
+                    context_id=context_id,
                     is_multiturn=is_multiturn,
                     status="failed",
+                    final=True,
                     agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            return TaskStateResult(
+                status=TaskState.failed,
+                error=error_msg,
+                history=new_messages,
+            )
+
+        except Exception as e:
+            error_msg = f"Unexpected error during polling: {e!s}"
+
+            error_message = Message(
+                role=Role.agent,
+                message_id=str(uuid.uuid4()),
+                parts=[Part(root=TextPart(text=error_msg))],
+                context_id=context_id,
+                task_id=task_id,
+            )
+            new_messages.append(error_message)
+
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=str(e),
+                    error_type="unexpected_error",
+                    a2a_agent_name=a2a_agent_name,
+                    operation="polling",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AResponseReceivedEvent(
+                    response=error_msg,
+                    turn_number=turn_number,
+                    context_id=context_id,
+                    is_multiturn=is_multiturn,
+                    status="failed",
+                    final=True,
+                    agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
                 ),
             )
             return TaskStateResult(

lib/crewai/src/crewai/a2a/updates/push_notifications/handler.py

@@ -29,6 +29,7 @@ from crewai.a2a.updates.base import (
 )
 from crewai.events.event_bus import crewai_event_bus
 from crewai.events.types.a2a_events import (
+    A2AConnectionErrorEvent,
     A2APushNotificationRegisteredEvent,
     A2APushNotificationTimeoutEvent,
     A2AResponseReceivedEvent,
@@ -48,6 +49,11 @@ async def _wait_for_push_result(
     timeout: float,
     poll_interval: float,
     agent_branch: Any | None = None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    context_id: str | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
 ) -> A2ATask | None:
     """Wait for push notification result.
 
@@ -57,6 +63,11 @@ async def _wait_for_push_result(
         timeout: Max seconds to wait.
         poll_interval: Seconds between polling attempts.
         agent_branch: Agent tree branch for logging.
+        from_task: Optional CrewAI Task object for event metadata.
+        from_agent: Optional CrewAI Agent object for event metadata.
+        context_id: A2A context ID for correlation.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent.
 
     Returns:
         Final task object, or None if timeout.
@@ -72,7 +83,12 @@ async def _wait_for_push_result(
             agent_branch,
             A2APushNotificationTimeoutEvent(
                 task_id=task_id,
+                context_id=context_id,
                 timeout_seconds=timeout,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
             ),
         )
 
@@ -115,18 +131,56 @@ class PushNotificationHandler:
         agent_role = kwargs.get("agent_role")
         context_id = kwargs.get("context_id")
         task_id = kwargs.get("task_id")
+        endpoint = kwargs.get("endpoint")
+        a2a_agent_name = kwargs.get("a2a_agent_name")
+        from_task = kwargs.get("from_task")
+        from_agent = kwargs.get("from_agent")
 
         if config is None:
+            error_msg = (
+                "PushNotificationConfig is required for push notification handler"
+            )
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=error_msg,
+                    error_type="configuration_error",
+                    a2a_agent_name=a2a_agent_name,
+                    operation="push_notification",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
             return TaskStateResult(
                 status=TaskState.failed,
-                error="PushNotificationConfig is required for push notification handler",
+                error=error_msg,
                 history=new_messages,
             )
 
         if result_store is None:
+            error_msg = (
+                "PushNotificationResultStore is required for push notification handler"
+            )
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=error_msg,
+                    error_type="configuration_error",
+                    a2a_agent_name=a2a_agent_name,
+                    operation="push_notification",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
             return TaskStateResult(
                 status=TaskState.failed,
-                error="PushNotificationResultStore is required for push notification handler",
+                error=error_msg,
                 history=new_messages,
             )
 
@@ -138,6 +192,11 @@ class PushNotificationHandler:
                 turn_number=turn_number,
                 is_multiturn=is_multiturn,
                 agent_role=agent_role,
+                from_task=from_task,
+                from_agent=from_agent,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                context_id=context_id,
             )
 
             if not isinstance(result_or_task_id, str):
@@ -149,7 +208,12 @@ class PushNotificationHandler:
                 agent_branch,
                 A2APushNotificationRegisteredEvent(
                     task_id=task_id,
+                    context_id=context_id,
                     callback_url=str(config.url),
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
                 ),
             )
 
@@ -165,6 +229,11 @@ class PushNotificationHandler:
                 timeout=polling_timeout,
                 poll_interval=polling_interval,
                 agent_branch=agent_branch,
+                from_task=from_task,
+                from_agent=from_agent,
+                context_id=context_id,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
             )
 
             if final_task is None:
@@ -181,6 +250,10 @@ class PushNotificationHandler:
                 turn_number=turn_number,
                 is_multiturn=is_multiturn,
                 agent_role=agent_role,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                from_task=from_task,
+                from_agent=from_agent,
             )
             if result:
                 return result
@@ -203,14 +276,83 @@ class PushNotificationHandler:
             )
             new_messages.append(error_message)
 
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=str(e),
+                    error_type="http_error",
+                    status_code=e.status_code,
+                    a2a_agent_name=a2a_agent_name,
+                    operation="push_notification",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
             crewai_event_bus.emit(
                 agent_branch,
                 A2AResponseReceivedEvent(
                     response=error_msg,
                     turn_number=turn_number,
+                    context_id=context_id,
                     is_multiturn=is_multiturn,
                     status="failed",
+                    final=True,
                     agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            return TaskStateResult(
+                status=TaskState.failed,
+                error=error_msg,
+                history=new_messages,
+            )
+
+        except Exception as e:
+            error_msg = f"Unexpected error during push notification: {e!s}"
+
+            error_message = Message(
+                role=Role.agent,
+                message_id=str(uuid.uuid4()),
+                parts=[Part(root=TextPart(text=error_msg))],
+                context_id=context_id,
+                task_id=task_id,
+            )
+            new_messages.append(error_message)
+
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=str(e),
+                    error_type="unexpected_error",
+                    a2a_agent_name=a2a_agent_name,
+                    operation="push_notification",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AResponseReceivedEvent(
+                    response=error_msg,
+                    turn_number=turn_number,
+                    context_id=context_id,
+                    is_multiturn=is_multiturn,
+                    status="failed",
+                    final=True,
+                    agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
                 ),
             )
             return TaskStateResult(

lib/crewai/src/crewai/a2a/updates/streaming/handler.py

@@ -26,7 +26,13 @@ from crewai.a2a.task_helpers import (
 )
 from crewai.a2a.updates.base import StreamingHandlerKwargs
 from crewai.events.event_bus import crewai_event_bus
-from crewai.events.types.a2a_events import A2AResponseReceivedEvent
+from crewai.events.types.a2a_events import (
+    A2AArtifactReceivedEvent,
+    A2AConnectionErrorEvent,
+    A2AResponseReceivedEvent,
+    A2AStreamingChunkEvent,
+    A2AStreamingStartedEvent,
+)
 
 
 class StreamingHandler:
@@ -57,19 +63,57 @@ class StreamingHandler:
         turn_number = kwargs.get("turn_number", 0)
         is_multiturn = kwargs.get("is_multiturn", False)
         agent_role = kwargs.get("agent_role")
+        endpoint = kwargs.get("endpoint")
+        a2a_agent_name = kwargs.get("a2a_agent_name")
+        from_task = kwargs.get("from_task")
+        from_agent = kwargs.get("from_agent")
+        agent_branch = kwargs.get("agent_branch")
 
         result_parts: list[str] = []
         final_result: TaskStateResult | None = None
         event_stream = client.send_message(message)
+        chunk_index = 0
+
+        crewai_event_bus.emit(
+            agent_branch,
+            A2AStreamingStartedEvent(
+                task_id=task_id,
+                context_id=context_id,
+                endpoint=endpoint or "",
+                a2a_agent_name=a2a_agent_name,
+                turn_number=turn_number,
+                is_multiturn=is_multiturn,
+                agent_role=agent_role,
+                from_task=from_task,
+                from_agent=from_agent,
+            ),
+        )
 
         try:
             async for event in event_stream:
                 if isinstance(event, Message):
                     new_messages.append(event)
+                    message_context_id = event.context_id or context_id
                     for part in event.parts:
                         if part.root.kind == "text":
                             text = part.root.text
                             result_parts.append(text)
+                            crewai_event_bus.emit(
+                                agent_branch,
+                                A2AStreamingChunkEvent(
+                                    task_id=event.task_id or task_id,
+                                    context_id=message_context_id,
+                                    chunk=text,
+                                    chunk_index=chunk_index,
+                                    endpoint=endpoint,
+                                    a2a_agent_name=a2a_agent_name,
+                                    turn_number=turn_number,
+                                    is_multiturn=is_multiturn,
+                                    from_task=from_task,
+                                    from_agent=from_agent,
+                                ),
+                            )
+                            chunk_index += 1
 
                 elif isinstance(event, tuple):
                     a2a_task, update = event
@@ -81,10 +125,51 @@ class StreamingHandler:
                             for part in artifact.parts
                             if part.root.kind == "text"
                         )
+                        artifact_size = None
+                        if artifact.parts:
+                            artifact_size = sum(
+                                len(p.root.text.encode("utf-8"))
+                                if p.root.kind == "text"
+                                else len(getattr(p.root, "data", b""))
+                                for p in artifact.parts
+                            )
+                        effective_context_id = a2a_task.context_id or context_id
+                        crewai_event_bus.emit(
+                            agent_branch,
+                            A2AArtifactReceivedEvent(
+                                task_id=a2a_task.id,
+                                artifact_id=artifact.artifact_id,
+                                artifact_name=artifact.name,
+                                artifact_description=artifact.description,
+                                mime_type=artifact.parts[0].root.kind
+                                if artifact.parts
+                                else None,
+                                size_bytes=artifact_size,
+                                append=update.append or False,
+                                last_chunk=update.last_chunk or False,
+                                endpoint=endpoint,
+                                a2a_agent_name=a2a_agent_name,
+                                context_id=effective_context_id,
+                                turn_number=turn_number,
+                                is_multiturn=is_multiturn,
+                                from_task=from_task,
+                                from_agent=from_agent,
+                            ),
+                        )
 
                     is_final_update = False
                     if isinstance(update, TaskStatusUpdateEvent):
                         is_final_update = update.final
+                        if (
+                            update.status
+                            and update.status.message
+                            and update.status.message.parts
+                        ):
+                            result_parts.extend(
+                                part.root.text
+                                for part in update.status.message.parts
+                                if part.root.kind == "text" and part.root.text
+                            )
 
                     if (
                         not is_final_update
@@ -101,6 +186,11 @@ class StreamingHandler:
                         is_multiturn=is_multiturn,
                         agent_role=agent_role,
                         result_parts=result_parts,
+                        endpoint=endpoint,
+                        a2a_agent_name=a2a_agent_name,
+                        from_task=from_task,
+                        from_agent=from_agent,
+                        is_final=is_final_update,
                     )
                     if final_result:
                         break
@@ -118,13 +208,82 @@ class StreamingHandler:
             new_messages.append(error_message)
 
             crewai_event_bus.emit(
-                None,
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=str(e),
+                    error_type="http_error",
+                    status_code=e.status_code,
+                    a2a_agent_name=a2a_agent_name,
+                    operation="streaming",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            crewai_event_bus.emit(
+                agent_branch,
                 A2AResponseReceivedEvent(
                     response=error_msg,
                     turn_number=turn_number,
+                    context_id=context_id,
                     is_multiturn=is_multiturn,
                     status="failed",
+                    final=True,
                     agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            return TaskStateResult(
+                status=TaskState.failed,
+                error=error_msg,
+                history=new_messages,
+            )
+
+        except Exception as e:
+            error_msg = f"Unexpected error during streaming: {e!s}"
+
+            error_message = Message(
+                role=Role.agent,
+                message_id=str(uuid.uuid4()),
+                parts=[Part(root=TextPart(text=error_msg))],
+                context_id=context_id,
+                task_id=task_id,
+            )
+            new_messages.append(error_message)
+
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint or "",
+                    error=str(e),
+                    error_type="unexpected_error",
+                    a2a_agent_name=a2a_agent_name,
+                    operation="streaming",
+                    context_id=context_id,
+                    task_id=task_id,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                ),
+            )
+            crewai_event_bus.emit(
+                agent_branch,
+                A2AResponseReceivedEvent(
+                    response=error_msg,
+                    turn_number=turn_number,
+                    context_id=context_id,
+                    is_multiturn=is_multiturn,
+                    status="failed",
+                    final=True,
+                    agent_role=agent_role,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    from_task=from_task,
+                    from_agent=from_agent,
                 ),
             )
             return TaskStateResult(
@@ -136,7 +295,23 @@ class StreamingHandler:
         finally:
             aclose = getattr(event_stream, "aclose", None)
             if aclose:
-                await aclose()
+                try:
+                    await aclose()
+                except Exception as close_error:
+                    crewai_event_bus.emit(
+                        agent_branch,
+                        A2AConnectionErrorEvent(
+                            endpoint=endpoint or "",
+                            error=str(close_error),
+                            error_type="stream_close_error",
+                            a2a_agent_name=a2a_agent_name,
+                            operation="stream_close",
+                            context_id=context_id,
+                            task_id=task_id,
+                            from_task=from_task,
+                            from_agent=from_agent,
+                        ),
+                    )
 
         if final_result:
             return final_result
@@ -145,5 +320,5 @@ class StreamingHandler:
             status=TaskState.completed,
             result=" ".join(result_parts) if result_parts else "",
             history=new_messages,
-            agent_card=agent_card,
+            agent_card=agent_card.model_dump(exclude_none=True),
         )

lib/crewai/src/crewai/a2a/utils/agent_card.py

@@ -23,6 +23,12 @@ from crewai.a2a.auth.utils import (
 )
 from crewai.a2a.config import A2AServerConfig
 from crewai.crew import Crew
+from crewai.events.event_bus import crewai_event_bus
+from crewai.events.types.a2a_events import (
+    A2AAgentCardFetchedEvent,
+    A2AAuthenticationFailedEvent,
+    A2AConnectionErrorEvent,
+)
 
 
 if TYPE_CHECKING:
@@ -183,6 +189,8 @@ async def _afetch_agent_card_impl(
     timeout: int,
 ) -> AgentCard:
     """Internal async implementation of AgentCard fetching."""
+    start_time = time.perf_counter()
+
     if "/.well-known/agent-card.json" in endpoint:
         base_url = endpoint.replace("/.well-known/agent-card.json", "")
         agent_card_path = "/.well-known/agent-card.json"
@@ -217,9 +225,29 @@ async def _afetch_agent_card_impl(
             )
             response.raise_for_status()
 
-            return AgentCard.model_validate(response.json())
+            agent_card = AgentCard.model_validate(response.json())
+            fetch_time_ms = (time.perf_counter() - start_time) * 1000
+            agent_card_dict = agent_card.model_dump(exclude_none=True)
+
+            crewai_event_bus.emit(
+                None,
+                A2AAgentCardFetchedEvent(
+                    endpoint=endpoint,
+                    a2a_agent_name=agent_card.name,
+                    agent_card=agent_card_dict,
+                    protocol_version=agent_card.protocol_version,
+                    provider=agent_card_dict.get("provider"),
+                    cached=False,
+                    fetch_time_ms=fetch_time_ms,
+                ),
+            )
+
+            return agent_card
 
         except httpx.HTTPStatusError as e:
+            elapsed_ms = (time.perf_counter() - start_time) * 1000
+            response_body = e.response.text[:1000] if e.response.text else None
+
             if e.response.status_code == 401:
                 error_details = ["Authentication failed"]
                 www_auth = e.response.headers.get("WWW-Authenticate")
@@ -228,7 +256,93 @@ async def _afetch_agent_card_impl(
                 if not auth:
                     error_details.append("No auth scheme provided")
                 msg = " | ".join(error_details)
+
+                auth_type = type(auth).__name__ if auth else None
+                crewai_event_bus.emit(
+                    None,
+                    A2AAuthenticationFailedEvent(
+                        endpoint=endpoint,
+                        auth_type=auth_type,
+                        error=msg,
+                        status_code=401,
+                        metadata={
+                            "elapsed_ms": elapsed_ms,
+                            "response_body": response_body,
+                            "www_authenticate": www_auth,
+                            "request_url": str(e.request.url),
+                        },
+                    ),
+                )
+
                 raise A2AClientHTTPError(401, msg) from e
+
+            crewai_event_bus.emit(
+                None,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint,
+                    error=str(e),
+                    error_type="http_error",
+                    status_code=e.response.status_code,
+                    operation="fetch_agent_card",
+                    metadata={
+                        "elapsed_ms": elapsed_ms,
+                        "response_body": response_body,
+                        "request_url": str(e.request.url),
+                    },
+                ),
+            )
+            raise
+
+        except httpx.TimeoutException as e:
+            elapsed_ms = (time.perf_counter() - start_time) * 1000
+            crewai_event_bus.emit(
+                None,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint,
+                    error=str(e),
+                    error_type="timeout",
+                    operation="fetch_agent_card",
+                    metadata={
+                        "elapsed_ms": elapsed_ms,
+                        "timeout_config": timeout,
+                        "request_url": str(e.request.url) if e.request else None,
+                    },
+                ),
+            )
+            raise
+
+        except httpx.ConnectError as e:
+            elapsed_ms = (time.perf_counter() - start_time) * 1000
+            crewai_event_bus.emit(
+                None,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint,
+                    error=str(e),
+                    error_type="connection_error",
+                    operation="fetch_agent_card",
+                    metadata={
+                        "elapsed_ms": elapsed_ms,
+                        "request_url": str(e.request.url) if e.request else None,
+                    },
+                ),
+            )
+            raise
+
+        except httpx.RequestError as e:
+            elapsed_ms = (time.perf_counter() - start_time) * 1000
+            crewai_event_bus.emit(
+                None,
+                A2AConnectionErrorEvent(
+                    endpoint=endpoint,
+                    error=str(e),
+                    error_type="request_error",
+                    operation="fetch_agent_card",
+                    metadata={
+                        "elapsed_ms": elapsed_ms,
+                        "request_url": str(e.request.url) if e.request else None,
+                    },
+                ),
+            )
             raise
 
 

lib/crewai/src/crewai/a2a/utils/delegation.py

@@ -88,6 +88,9 @@ def execute_a2a_delegation(
     response_model: type[BaseModel] | None = None,
     turn_number: int | None = None,
     updates: UpdateConfig | None = None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    skill_id: str | None = None,
 ) -> TaskStateResult:
     """Execute a task delegation to a remote A2A agent synchronously.
 
@@ -129,6 +132,9 @@ def execute_a2a_delegation(
         response_model: Optional Pydantic model for structured outputs.
         turn_number: Optional turn number for multi-turn conversations.
         updates: Update mechanism config from A2AConfig.updates.
+        from_task: Optional CrewAI Task object for event metadata.
+        from_agent: Optional CrewAI Agent object for event metadata.
+        skill_id: Optional skill ID to target a specific agent capability.
 
     Returns:
         TaskStateResult with status, result/error, history, and agent_card.
@@ -156,10 +162,16 @@ def execute_a2a_delegation(
                 transport_protocol=transport_protocol,
                 turn_number=turn_number,
                 updates=updates,
+                from_task=from_task,
+                from_agent=from_agent,
+                skill_id=skill_id,
             )
         )
     finally:
-        loop.close()
+        try:
+            loop.run_until_complete(loop.shutdown_asyncgens())
+        finally:
+            loop.close()
 
 
 async def aexecute_a2a_delegation(
@@ -181,6 +193,9 @@ async def aexecute_a2a_delegation(
     response_model: type[BaseModel] | None = None,
     turn_number: int | None = None,
     updates: UpdateConfig | None = None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    skill_id: str | None = None,
 ) -> TaskStateResult:
     """Execute a task delegation to a remote A2A agent asynchronously.
 
@@ -222,6 +237,9 @@ async def aexecute_a2a_delegation(
         response_model: Optional Pydantic model for structured outputs.
         turn_number: Optional turn number for multi-turn conversations.
         updates: Update mechanism config from A2AConfig.updates.
+        from_task: Optional CrewAI Task object for event metadata.
+        from_agent: Optional CrewAI Agent object for event metadata.
+        skill_id: Optional skill ID to target a specific agent capability.
 
     Returns:
         TaskStateResult with status, result/error, history, and agent_card.
@@ -233,17 +251,6 @@ async def aexecute_a2a_delegation(
     if turn_number is None:
         turn_number = len([m for m in conversation_history if m.role == Role.user]) + 1
 
-    crewai_event_bus.emit(
-        agent_branch,
-        A2ADelegationStartedEvent(
-            endpoint=endpoint,
-            task_description=task_description,
-            agent_id=agent_id,
-            is_multiturn=is_multiturn,
-            turn_number=turn_number,
-        ),
-    )
-
     result = await _aexecute_a2a_delegation_impl(
         endpoint=endpoint,
         auth=auth,
@@ -264,15 +271,28 @@ async def aexecute_a2a_delegation(
         response_model=response_model,
         updates=updates,
         transport_protocol=transport_protocol,
+        from_task=from_task,
+        from_agent=from_agent,
+        skill_id=skill_id,
     )
 
+    agent_card_data: dict[str, Any] = result.get("agent_card") or {}
     crewai_event_bus.emit(
         agent_branch,
         A2ADelegationCompletedEvent(
             status=result["status"],
             result=result.get("result"),
             error=result.get("error"),
+            context_id=context_id,
             is_multiturn=is_multiturn,
+            endpoint=endpoint,
+            a2a_agent_name=result.get("a2a_agent_name"),
+            agent_card=agent_card_data,
+            provider=agent_card_data.get("provider"),
+            metadata=metadata,
+            extensions=list(extensions.keys()) if extensions else None,
+            from_task=from_task,
+            from_agent=from_agent,
         ),
     )
 
@@ -299,6 +319,9 @@ async def _aexecute_a2a_delegation_impl(
     agent_role: str | None,
     response_model: type[BaseModel] | None,
     updates: UpdateConfig | None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    skill_id: str | None = None,
 ) -> TaskStateResult:
     """Internal async implementation of A2A delegation."""
     if auth:
@@ -331,6 +354,28 @@ async def _aexecute_a2a_delegation_impl(
     if agent_card.name:
         a2a_agent_name = agent_card.name
 
+    agent_card_dict = agent_card.model_dump(exclude_none=True)
+    crewai_event_bus.emit(
+        agent_branch,
+        A2ADelegationStartedEvent(
+            endpoint=endpoint,
+            task_description=task_description,
+            agent_id=agent_id or endpoint,
+            context_id=context_id,
+            is_multiturn=is_multiturn,
+            turn_number=turn_number,
+            a2a_agent_name=a2a_agent_name,
+            agent_card=agent_card_dict,
+            protocol_version=agent_card.protocol_version,
+            provider=agent_card_dict.get("provider"),
+            skill_id=skill_id,
+            metadata=metadata,
+            extensions=list(extensions.keys()) if extensions else None,
+            from_task=from_task,
+            from_agent=from_agent,
+        ),
+    )
+
     if turn_number == 1:
         agent_id_for_event = agent_id or endpoint
         crewai_event_bus.emit(
@@ -338,7 +383,17 @@ async def _aexecute_a2a_delegation_impl(
             A2AConversationStartedEvent(
                 agent_id=agent_id_for_event,
                 endpoint=endpoint,
+                context_id=context_id,
                 a2a_agent_name=a2a_agent_name,
+                agent_card=agent_card_dict,
+                protocol_version=agent_card.protocol_version,
+                provider=agent_card_dict.get("provider"),
+                skill_id=skill_id,
+                reference_task_ids=reference_task_ids,
+                metadata=metadata,
+                extensions=list(extensions.keys()) if extensions else None,
+                from_task=from_task,
+                from_agent=from_agent,
             ),
         )
 
@@ -364,6 +419,10 @@ async def _aexecute_a2a_delegation_impl(
             }
         )
 
+    message_metadata = metadata.copy() if metadata else {}
+    if skill_id:
+        message_metadata["skill_id"] = skill_id
+
     message = Message(
         role=Role.user,
         message_id=str(uuid.uuid4()),
@@ -371,7 +430,7 @@ async def _aexecute_a2a_delegation_impl(
         context_id=context_id,
         task_id=task_id,
         reference_task_ids=reference_task_ids,
-        metadata=metadata,
+        metadata=message_metadata if message_metadata else None,
         extensions=extensions,
     )
 
@@ -381,8 +440,17 @@ async def _aexecute_a2a_delegation_impl(
         A2AMessageSentEvent(
             message=message_text,
             turn_number=turn_number,
+            context_id=context_id,
+            message_id=message.message_id,
             is_multiturn=is_multiturn,
             agent_role=agent_role,
+            endpoint=endpoint,
+            a2a_agent_name=a2a_agent_name,
+            skill_id=skill_id,
+            metadata=message_metadata if message_metadata else None,
+            extensions=list(extensions.keys()) if extensions else None,
+            from_task=from_task,
+            from_agent=from_agent,
         ),
     )
 
@@ -397,6 +465,9 @@ async def _aexecute_a2a_delegation_impl(
         "task_id": task_id,
         "endpoint": endpoint,
         "agent_branch": agent_branch,
+        "a2a_agent_name": a2a_agent_name,
+        "from_task": from_task,
+        "from_agent": from_agent,
     }
 
     if isinstance(updates, PollingConfig):
@@ -434,13 +505,16 @@ async def _aexecute_a2a_delegation_impl(
         use_polling=use_polling,
         push_notification_config=push_config_for_client,
     ) as client:
-        return await handler.execute(
+        result = await handler.execute(
             client=client,
             message=message,
             new_messages=new_messages,
             agent_card=agent_card,
             **handler_kwargs,
         )
+        result["a2a_agent_name"] = a2a_agent_name
+        result["agent_card"] = agent_card.model_dump(exclude_none=True)
+        return result
 
 
 @asynccontextmanager

lib/crewai/src/crewai/a2a/utils/task.py

@@ -3,11 +3,14 @@
 from __future__ import annotations
 
 import asyncio
+import base64
 from collections.abc import Callable, Coroutine
+from datetime import datetime
 from functools import wraps
 import logging
 import os
 from typing import TYPE_CHECKING, Any, ParamSpec, TypeVar, cast
+from urllib.parse import urlparse
 
 from a2a.server.agent_execution import RequestContext
 from a2a.server.events import EventQueue
@@ -45,7 +48,14 @@ T = TypeVar("T")
 
 
 def _parse_redis_url(url: str) -> dict[str, Any]:
-    from urllib.parse import urlparse
+    """Parse a Redis URL into aiocache configuration.
+
+    Args:
+        url: Redis connection URL (e.g., redis://localhost:6379/0).
+
+    Returns:
+        Configuration dict for aiocache.RedisCache.
+    """
 
     parsed = urlparse(url)
     config: dict[str, Any] = {
@@ -127,7 +137,7 @@ def cancellable(
                 async for message in pubsub.listen():
                     if message["type"] == "message":
                         return True
-            except Exception as e:
+            except (OSError, ConnectionError) as e:
                 logger.warning("Cancel watcher error for task_id=%s: %s", task_id, e)
                 return await poll_for_cancel()
             return False
@@ -183,7 +193,12 @@ async def execute(
         msg = "task_id and context_id are required"
         crewai_event_bus.emit(
             agent,
-            A2AServerTaskFailedEvent(a2a_task_id="", a2a_context_id="", error=msg),
+            A2AServerTaskFailedEvent(
+                task_id="",
+                context_id="",
+                error=msg,
+                from_agent=agent,
+            ),
         )
         raise ServerError(InvalidParamsError(message=msg)) from None
 
@@ -195,7 +210,12 @@ async def execute(
 
     crewai_event_bus.emit(
         agent,
-        A2AServerTaskStartedEvent(a2a_task_id=task_id, a2a_context_id=context_id),
+        A2AServerTaskStartedEvent(
+            task_id=task_id,
+            context_id=context_id,
+            from_task=task,
+            from_agent=agent,
+        ),
     )
 
     try:
@@ -215,20 +235,33 @@ async def execute(
         crewai_event_bus.emit(
             agent,
             A2AServerTaskCompletedEvent(
-                a2a_task_id=task_id, a2a_context_id=context_id, result=str(result)
+                task_id=task_id,
+                context_id=context_id,
+                result=str(result),
+                from_task=task,
+                from_agent=agent,
             ),
         )
     except asyncio.CancelledError:
         crewai_event_bus.emit(
             agent,
-            A2AServerTaskCanceledEvent(a2a_task_id=task_id, a2a_context_id=context_id),
+            A2AServerTaskCanceledEvent(
+                task_id=task_id,
+                context_id=context_id,
+                from_task=task,
+                from_agent=agent,
+            ),
         )
         raise
     except Exception as e:
         crewai_event_bus.emit(
             agent,
             A2AServerTaskFailedEvent(
-                a2a_task_id=task_id, a2a_context_id=context_id, error=str(e)
+                task_id=task_id,
+                context_id=context_id,
+                error=str(e),
+                from_task=task,
+                from_agent=agent,
             ),
         )
         raise ServerError(
@@ -282,3 +315,85 @@ async def cancel(
         context.current_task.status = TaskStatus(state=TaskState.canceled)
         return context.current_task
     return None
+
+
+def list_tasks(
+    tasks: list[A2ATask],
+    context_id: str | None = None,
+    status: TaskState | None = None,
+    status_timestamp_after: datetime | None = None,
+    page_size: int = 50,
+    page_token: str | None = None,
+    history_length: int | None = None,
+    include_artifacts: bool = False,
+) -> tuple[list[A2ATask], str | None, int]:
+    """Filter and paginate A2A tasks.
+
+    Provides filtering by context, status, and timestamp, along with
+    cursor-based pagination. This is a pure utility function that operates
+    on an in-memory list of tasks - storage retrieval is handled separately.
+
+    Args:
+        tasks: All tasks to filter.
+        context_id: Filter by context ID to get tasks in a conversation.
+        status: Filter by task state (e.g., completed, working).
+        status_timestamp_after: Filter to tasks updated after this time.
+        page_size: Maximum tasks per page (default 50).
+        page_token: Base64-encoded cursor from previous response.
+        history_length: Limit history messages per task (None = full history).
+        include_artifacts: Whether to include task artifacts (default False).
+
+    Returns:
+        Tuple of (filtered_tasks, next_page_token, total_count).
+        - filtered_tasks: Tasks matching filters, paginated and trimmed.
+        - next_page_token: Token for next page, or None if no more pages.
+        - total_count: Total number of tasks matching filters (before pagination).
+    """
+    filtered: list[A2ATask] = []
+    for task in tasks:
+        if context_id and task.context_id != context_id:
+            continue
+        if status and task.status.state != status:
+            continue
+        if status_timestamp_after and task.status.timestamp:
+            ts = datetime.fromisoformat(task.status.timestamp.replace("Z", "+00:00"))
+            if ts <= status_timestamp_after:
+                continue
+        filtered.append(task)
+
+    def get_timestamp(t: A2ATask) -> datetime:
+        """Extract timestamp from task status for sorting."""
+        if t.status.timestamp is None:
+            return datetime.min
+        return datetime.fromisoformat(t.status.timestamp.replace("Z", "+00:00"))
+
+    filtered.sort(key=get_timestamp, reverse=True)
+    total = len(filtered)
+
+    start = 0
+    if page_token:
+        try:
+            cursor_id = base64.b64decode(page_token).decode()
+            for idx, task in enumerate(filtered):
+                if task.id == cursor_id:
+                    start = idx + 1
+                    break
+        except (ValueError, UnicodeDecodeError):
+            pass
+
+    page = filtered[start : start + page_size]
+
+    result: list[A2ATask] = []
+    for task in page:
+        task = task.model_copy(deep=True)
+        if history_length is not None and task.history:
+            task.history = task.history[-history_length:]
+        if not include_artifacts:
+            task.artifacts = None
+        result.append(task)
+
+    next_token: str | None = None
+    if result and len(result) == page_size:
+        next_token = base64.b64encode(result[-1].id.encode()).decode()
+
+    return result, next_token, total

lib/crewai/src/crewai/a2a/wrapper.py

@@ -6,9 +6,10 @@ Wraps agent classes with A2A delegation capabilities.
 from __future__ import annotations
 
 import asyncio
-from collections.abc import Callable, Coroutine
+from collections.abc import Callable, Coroutine, Mapping
 from concurrent.futures import ThreadPoolExecutor, as_completed
 from functools import wraps
+import json
 from types import MethodType
 from typing import TYPE_CHECKING, Any
 
@@ -189,7 +190,7 @@ def _execute_task_with_a2a(
     a2a_agents: list[A2AConfig | A2AClientConfig],
     original_fn: Callable[..., str],
     task: Task,
-    agent_response_model: type[BaseModel],
+    agent_response_model: type[BaseModel] | None,
     context: str | None,
     tools: list[BaseTool] | None,
     extension_registry: ExtensionRegistry,
@@ -277,7 +278,7 @@ def _execute_task_with_a2a(
 def _augment_prompt_with_a2a(
     a2a_agents: list[A2AConfig | A2AClientConfig],
     task_description: str,
-    agent_cards: dict[str, AgentCard],
+    agent_cards: Mapping[str, AgentCard | dict[str, Any]],
     conversation_history: list[Message] | None = None,
     turn_num: int = 0,
     max_turns: int | None = None,
@@ -309,7 +310,15 @@ def _augment_prompt_with_a2a(
     for config in a2a_agents:
         if config.endpoint in agent_cards:
             card = agent_cards[config.endpoint]
-            agents_text += f"\n{card.model_dump_json(indent=2, exclude_none=True, include={'description', 'url', 'skills'})}\n"
+            if isinstance(card, dict):
+                filtered = {
+                    k: v
+                    for k, v in card.items()
+                    if k in {"description", "url", "skills"} and v is not None
+                }
+                agents_text += f"\n{json.dumps(filtered, indent=2)}\n"
+            else:
+                agents_text += f"\n{card.model_dump_json(indent=2, exclude_none=True, include={'description', 'url', 'skills'})}\n"
 
     failed_agents = failed_agents or {}
     if failed_agents:
@@ -377,7 +386,7 @@ IMPORTANT: You have the ability to delegate this task to remote A2A agents.
 
 
 def _parse_agent_response(
-    raw_result: str | dict[str, Any], agent_response_model: type[BaseModel]
+    raw_result: str | dict[str, Any], agent_response_model: type[BaseModel] | None
 ) -> BaseModel | str | dict[str, Any]:
     """Parse LLM output as AgentResponse or return raw agent response."""
     if agent_response_model:
@@ -394,6 +403,11 @@ def _parse_agent_response(
 def _handle_max_turns_exceeded(
     conversation_history: list[Message],
     max_turns: int,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    agent_card: dict[str, Any] | None = None,
 ) -> str:
     """Handle the case when max turns is exceeded.
 
@@ -421,6 +435,11 @@ def _handle_max_turns_exceeded(
                         final_result=final_message,
                         error=None,
                         total_turns=max_turns,
+                        from_task=from_task,
+                        from_agent=from_agent,
+                        endpoint=endpoint,
+                        a2a_agent_name=a2a_agent_name,
+                        agent_card=agent_card,
                     ),
                 )
                 return final_message
@@ -432,6 +451,11 @@ def _handle_max_turns_exceeded(
             final_result=None,
             error=f"Conversation exceeded maximum turns ({max_turns})",
             total_turns=max_turns,
+            from_task=from_task,
+            from_agent=from_agent,
+            endpoint=endpoint,
+            a2a_agent_name=a2a_agent_name,
+            agent_card=agent_card,
         ),
     )
     raise Exception(f"A2A conversation exceeded maximum turns ({max_turns})")
@@ -442,7 +466,12 @@ def _process_response_result(
     disable_structured_output: bool,
     turn_num: int,
     agent_role: str,
-    agent_response_model: type[BaseModel],
+    agent_response_model: type[BaseModel] | None,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    agent_card: dict[str, Any] | None = None,
 ) -> tuple[str | None, str | None]:
     """Process LLM response and determine next action.
 
@@ -461,6 +490,10 @@ def _process_response_result(
                 turn_number=final_turn_number,
                 is_multiturn=True,
                 agent_role=agent_role,
+                from_task=from_task,
+                from_agent=from_agent,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
             ),
         )
         crewai_event_bus.emit(
@@ -470,6 +503,11 @@ def _process_response_result(
                 final_result=result_text,
                 error=None,
                 total_turns=final_turn_number,
+                from_task=from_task,
+                from_agent=from_agent,
+                endpoint=endpoint,
+                a2a_agent_name=a2a_agent_name,
+                agent_card=agent_card,
             ),
         )
         return result_text, None
@@ -490,6 +528,10 @@ def _process_response_result(
                     turn_number=final_turn_number,
                     is_multiturn=True,
                     agent_role=agent_role,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
                 ),
             )
             crewai_event_bus.emit(
@@ -499,6 +541,11 @@ def _process_response_result(
                     final_result=str(llm_response.message),
                     error=None,
                     total_turns=final_turn_number,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    agent_card=agent_card,
                 ),
             )
             return str(llm_response.message), None
@@ -510,13 +557,15 @@ def _process_response_result(
 def _prepare_agent_cards_dict(
     a2a_result: TaskStateResult,
     agent_id: str,
-    agent_cards: dict[str, AgentCard] | None,
+    agent_cards: Mapping[str, AgentCard | dict[str, Any]] | None,
-) -> dict[str, AgentCard]:
+) -> dict[str, AgentCard | dict[str, Any]]:
     """Prepare agent cards dictionary from result and existing cards.
 
     Shared logic for both sync and async response handlers.
     """
-    agent_cards_dict = agent_cards or {}
+    agent_cards_dict: dict[str, AgentCard | dict[str, Any]] = (
+        dict(agent_cards) if agent_cards else {}
+    )
     if "agent_card" in a2a_result and agent_id not in agent_cards_dict:
         agent_cards_dict[agent_id] = a2a_result["agent_card"]
     return agent_cards_dict
@@ -529,7 +578,7 @@ def _prepare_delegation_context(
     original_task_description: str | None,
 ) -> tuple[
     list[A2AConfig | A2AClientConfig],
-    type[BaseModel],
+    type[BaseModel] | None,
     str,
     str,
     A2AConfig | A2AClientConfig,
@@ -598,6 +647,11 @@ def _handle_task_completion(
     reference_task_ids: list[str],
     agent_config: A2AConfig | A2AClientConfig,
     turn_num: int,
+    from_task: Any | None = None,
+    from_agent: Any | None = None,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    agent_card: dict[str, Any] | None = None,
 ) -> tuple[str | None, str | None, list[str]]:
     """Handle task completion state including reference task updates.
 
@@ -624,6 +678,11 @@ def _handle_task_completion(
                     final_result=result_text,
                     error=None,
                     total_turns=final_turn_number,
+                    from_task=from_task,
+                    from_agent=from_agent,
+                    endpoint=endpoint,
+                    a2a_agent_name=a2a_agent_name,
+                    agent_card=agent_card,
                 ),
             )
             return str(result_text), task_id_config, reference_task_ids
@@ -645,8 +704,11 @@ def _handle_agent_response_and_continue(
     original_fn: Callable[..., str],
     context: str | None,
     tools: list[BaseTool] | None,
-    agent_response_model: type[BaseModel],
+    agent_response_model: type[BaseModel] | None,
     remote_task_completed: bool = False,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    agent_card: dict[str, Any] | None = None,
 ) -> tuple[str | None, str | None]:
     """Handle A2A result and get CrewAI agent's response.
 
@@ -698,6 +760,11 @@ def _handle_agent_response_and_continue(
         turn_num=turn_num,
         agent_role=self.role,
         agent_response_model=agent_response_model,
+        from_task=task,
+        from_agent=self,
+        endpoint=endpoint,
+        a2a_agent_name=a2a_agent_name,
+        agent_card=agent_card,
     )
 
 
@@ -750,6 +817,12 @@ def _delegate_to_a2a(
 
     conversation_history: list[Message] = []
 
+    current_agent_card = agent_cards.get(agent_id) if agent_cards else None
+    current_agent_card_dict = (
+        current_agent_card.model_dump() if current_agent_card else None
+    )
+    current_a2a_agent_name = current_agent_card.name if current_agent_card else None
+
     try:
         for turn_num in range(max_turns):
             console_formatter = getattr(crewai_event_bus, "_console", None)
@@ -777,6 +850,8 @@ def _delegate_to_a2a(
                 turn_number=turn_num + 1,
                 updates=agent_config.updates,
                 transport_protocol=agent_config.transport_protocol,
+                from_task=task,
+                from_agent=self,
             )
 
             conversation_history = a2a_result.get("history", [])
@@ -797,6 +872,11 @@ def _delegate_to_a2a(
                         reference_task_ids,
                         agent_config,
                         turn_num,
+                        from_task=task,
+                        from_agent=self,
+                        endpoint=agent_config.endpoint,
+                        a2a_agent_name=current_a2a_agent_name,
+                        agent_card=current_agent_card_dict,
                     )
                 )
                 if trusted_result is not None:
@@ -818,6 +898,9 @@ def _delegate_to_a2a(
                     tools=tools,
                     agent_response_model=agent_response_model,
                     remote_task_completed=(a2a_result["status"] == TaskState.completed),
+                    endpoint=agent_config.endpoint,
+                    a2a_agent_name=current_a2a_agent_name,
+                    agent_card=current_agent_card_dict,
                 )
 
                 if final_result is not None:
@@ -846,6 +929,9 @@ def _delegate_to_a2a(
                 tools=tools,
                 agent_response_model=agent_response_model,
                 remote_task_completed=False,
+                endpoint=agent_config.endpoint,
+                a2a_agent_name=current_a2a_agent_name,
+                agent_card=current_agent_card_dict,
             )
 
             if final_result is not None:
@@ -862,11 +948,24 @@ def _delegate_to_a2a(
                     final_result=None,
                     error=error_msg,
                     total_turns=turn_num + 1,
+                    from_task=task,
+                    from_agent=self,
+                    endpoint=agent_config.endpoint,
+                    a2a_agent_name=current_a2a_agent_name,
+                    agent_card=current_agent_card_dict,
                 ),
             )
             return f"A2A delegation failed: {error_msg}"
 
-        return _handle_max_turns_exceeded(conversation_history, max_turns)
+        return _handle_max_turns_exceeded(
+            conversation_history,
+            max_turns,
+            from_task=task,
+            from_agent=self,
+            endpoint=agent_config.endpoint,
+            a2a_agent_name=current_a2a_agent_name,
+            agent_card=current_agent_card_dict,
+        )
 
     finally:
         task.description = original_task_description
@@ -916,7 +1015,7 @@ async def _aexecute_task_with_a2a(
     a2a_agents: list[A2AConfig | A2AClientConfig],
     original_fn: Callable[..., Coroutine[Any, Any, str]],
     task: Task,
-    agent_response_model: type[BaseModel],
+    agent_response_model: type[BaseModel] | None,
     context: str | None,
     tools: list[BaseTool] | None,
     extension_registry: ExtensionRegistry,
@@ -1001,8 +1100,11 @@ async def _ahandle_agent_response_and_continue(
     original_fn: Callable[..., Coroutine[Any, Any, str]],
     context: str | None,
     tools: list[BaseTool] | None,
-    agent_response_model: type[BaseModel],
+    agent_response_model: type[BaseModel] | None,
     remote_task_completed: bool = False,
+    endpoint: str | None = None,
+    a2a_agent_name: str | None = None,
+    agent_card: dict[str, Any] | None = None,
 ) -> tuple[str | None, str | None]:
     """Async version of _handle_agent_response_and_continue."""
     agent_cards_dict = _prepare_agent_cards_dict(a2a_result, agent_id, agent_cards)
@@ -1032,6 +1134,11 @@ async def _ahandle_agent_response_and_continue(
         turn_num=turn_num,
         agent_role=self.role,
         agent_response_model=agent_response_model,
+        from_task=task,
+        from_agent=self,
+        endpoint=endpoint,
+        a2a_agent_name=a2a_agent_name,
+        agent_card=agent_card,
     )
 
 
@@ -1066,6 +1173,12 @@ async def _adelegate_to_a2a(
 
     conversation_history: list[Message] = []
 
+    current_agent_card = agent_cards.get(agent_id) if agent_cards else None
+    current_agent_card_dict = (
+        current_agent_card.model_dump() if current_agent_card else None
+    )
+    current_a2a_agent_name = current_agent_card.name if current_agent_card else None
+
     try:
         for turn_num in range(max_turns):
             console_formatter = getattr(crewai_event_bus, "_console", None)
@@ -1093,6 +1206,8 @@ async def _adelegate_to_a2a(
                 turn_number=turn_num + 1,
                 transport_protocol=agent_config.transport_protocol,
                 updates=agent_config.updates,
+                from_task=task,
+                from_agent=self,
             )
 
             conversation_history = a2a_result.get("history", [])
@@ -1113,6 +1228,11 @@ async def _adelegate_to_a2a(
                         reference_task_ids,
                         agent_config,
                         turn_num,
+                        from_task=task,
+                        from_agent=self,
+                        endpoint=agent_config.endpoint,
+                        a2a_agent_name=current_a2a_agent_name,
+                        agent_card=current_agent_card_dict,
                     )
                 )
                 if trusted_result is not None:
@@ -1134,6 +1254,9 @@ async def _adelegate_to_a2a(
                     tools=tools,
                     agent_response_model=agent_response_model,
                     remote_task_completed=(a2a_result["status"] == TaskState.completed),
+                    endpoint=agent_config.endpoint,
+                    a2a_agent_name=current_a2a_agent_name,
+                    agent_card=current_agent_card_dict,
                 )
 
                 if final_result is not None:
@@ -1161,6 +1284,9 @@ async def _adelegate_to_a2a(
                 context=context,
                 tools=tools,
                 agent_response_model=agent_response_model,
+                endpoint=agent_config.endpoint,
+                a2a_agent_name=current_a2a_agent_name,
+                agent_card=current_agent_card_dict,
             )
 
             if final_result is not None:
@@ -1177,11 +1303,24 @@ async def _adelegate_to_a2a(
                     final_result=None,
                     error=error_msg,
                     total_turns=turn_num + 1,
+                    from_task=task,
+                    from_agent=self,
+                    endpoint=agent_config.endpoint,
+                    a2a_agent_name=current_a2a_agent_name,
+                    agent_card=current_agent_card_dict,
                 ),
             )
             return f"A2A delegation failed: {error_msg}"
 
-        return _handle_max_turns_exceeded(conversation_history, max_turns)
+        return _handle_max_turns_exceeded(
+            conversation_history,
+            max_turns,
+            from_task=task,
+            from_agent=self,
+            endpoint=agent_config.endpoint,
+            a2a_agent_name=current_a2a_agent_name,
+            agent_card=current_agent_card_dict,
+        )
 
     finally:
         task.description = original_task_description

lib/crewai/src/crewai/events/event_types.py

@@ -1,19 +1,28 @@
 from crewai.events.types.a2a_events import (
+    A2AAgentCardFetchedEvent,
+    A2AArtifactReceivedEvent,
+    A2AAuthenticationFailedEvent,
+    A2AConnectionErrorEvent,
     A2AConversationCompletedEvent,
     A2AConversationStartedEvent,
     A2ADelegationCompletedEvent,
     A2ADelegationStartedEvent,
     A2AMessageSentEvent,
+    A2AParallelDelegationCompletedEvent,
+    A2AParallelDelegationStartedEvent,
     A2APollingStartedEvent,
     A2APollingStatusEvent,
     A2APushNotificationReceivedEvent,
     A2APushNotificationRegisteredEvent,
+    A2APushNotificationSentEvent,
     A2APushNotificationTimeoutEvent,
     A2AResponseReceivedEvent,
     A2AServerTaskCanceledEvent,
     A2AServerTaskCompletedEvent,
     A2AServerTaskFailedEvent,
     A2AServerTaskStartedEvent,
+    A2AStreamingChunkEvent,
+    A2AStreamingStartedEvent,
 )
 from crewai.events.types.agent_events import (
     AgentExecutionCompletedEvent,
@@ -93,7 +102,11 @@ from crewai.events.types.tool_usage_events import (
 
 
 EventTypes = (
-    A2AConversationCompletedEvent
+    A2AAgentCardFetchedEvent
+    | A2AArtifactReceivedEvent
+    | A2AAuthenticationFailedEvent
+    | A2AConnectionErrorEvent
+    | A2AConversationCompletedEvent
     | A2AConversationStartedEvent
     | A2ADelegationCompletedEvent
     | A2ADelegationStartedEvent
@@ -102,12 +115,17 @@ EventTypes = (
     | A2APollingStatusEvent
     | A2APushNotificationReceivedEvent
     | A2APushNotificationRegisteredEvent
+    | A2APushNotificationSentEvent
     | A2APushNotificationTimeoutEvent
     | A2AResponseReceivedEvent
     | A2AServerTaskCanceledEvent
     | A2AServerTaskCompletedEvent
     | A2AServerTaskFailedEvent
     | A2AServerTaskStartedEvent
+    | A2AStreamingChunkEvent
+    | A2AStreamingStartedEvent
+    | A2AParallelDelegationStartedEvent
+    | A2AParallelDelegationCompletedEvent
     | CrewKickoffStartedEvent
     | CrewKickoffCompletedEvent
     | CrewKickoffFailedEvent

lib/crewai/src/crewai/events/listeners/tracing/trace_listener.py

@@ -1,7 +1,7 @@
 """Trace collection listener for orchestrating trace collection."""
 
 import os
-from typing import Any, ClassVar, cast
+from typing import Any, ClassVar
 import uuid
 
 from typing_extensions import Self
@@ -18,6 +18,32 @@ from crewai.events.listeners.tracing.types import TraceEvent
 from crewai.events.listeners.tracing.utils import (
     safe_serialize_to_dict,
 )
+from crewai.events.types.a2a_events import (
+    A2AAgentCardFetchedEvent,
+    A2AArtifactReceivedEvent,
+    A2AAuthenticationFailedEvent,
+    A2AConnectionErrorEvent,
+    A2AConversationCompletedEvent,
+    A2AConversationStartedEvent,
+    A2ADelegationCompletedEvent,
+    A2ADelegationStartedEvent,
+    A2AMessageSentEvent,
+    A2AParallelDelegationCompletedEvent,
+    A2AParallelDelegationStartedEvent,
+    A2APollingStartedEvent,
+    A2APollingStatusEvent,
+    A2APushNotificationReceivedEvent,
+    A2APushNotificationRegisteredEvent,
+    A2APushNotificationSentEvent,
+    A2APushNotificationTimeoutEvent,
+    A2AResponseReceivedEvent,
+    A2AServerTaskCanceledEvent,
+    A2AServerTaskCompletedEvent,
+    A2AServerTaskFailedEvent,
+    A2AServerTaskStartedEvent,
+    A2AStreamingChunkEvent,
+    A2AStreamingStartedEvent,
+)
 from crewai.events.types.agent_events import (
     AgentExecutionCompletedEvent,
     AgentExecutionErrorEvent,
@@ -105,7 +131,7 @@ class TraceCollectionListener(BaseEventListener):
         """Create or return singleton instance."""
         if cls._instance is None:
             cls._instance = super().__new__(cls)
-        return cast(Self, cls._instance)
+        return cls._instance
 
     def __init__(
         self,
@@ -160,6 +186,7 @@ class TraceCollectionListener(BaseEventListener):
         self._register_flow_event_handlers(crewai_event_bus)
         self._register_context_event_handlers(crewai_event_bus)
         self._register_action_event_handlers(crewai_event_bus)
+        self._register_a2a_event_handlers(crewai_event_bus)
         self._register_system_event_handlers(crewai_event_bus)
 
         self._listeners_setup = True
@@ -439,6 +466,147 @@ class TraceCollectionListener(BaseEventListener):
         ) -> None:
             self._handle_action_event("knowledge_query_failed", source, event)
 
+    def _register_a2a_event_handlers(self, event_bus: CrewAIEventsBus) -> None:
+        """Register handlers for A2A (Agent-to-Agent) events."""
+
+        @event_bus.on(A2ADelegationStartedEvent)
+        def on_a2a_delegation_started(
+            source: Any, event: A2ADelegationStartedEvent
+        ) -> None:
+            self._handle_action_event("a2a_delegation_started", source, event)
+
+        @event_bus.on(A2ADelegationCompletedEvent)
+        def on_a2a_delegation_completed(
+            source: Any, event: A2ADelegationCompletedEvent
+        ) -> None:
+            self._handle_action_event("a2a_delegation_completed", source, event)
+
+        @event_bus.on(A2AConversationStartedEvent)
+        def on_a2a_conversation_started(
+            source: Any, event: A2AConversationStartedEvent
+        ) -> None:
+            self._handle_action_event("a2a_conversation_started", source, event)
+
+        @event_bus.on(A2AMessageSentEvent)
+        def on_a2a_message_sent(source: Any, event: A2AMessageSentEvent) -> None:
+            self._handle_action_event("a2a_message_sent", source, event)
+
+        @event_bus.on(A2AResponseReceivedEvent)
+        def on_a2a_response_received(
+            source: Any, event: A2AResponseReceivedEvent
+        ) -> None:
+            self._handle_action_event("a2a_response_received", source, event)
+
+        @event_bus.on(A2AConversationCompletedEvent)
+        def on_a2a_conversation_completed(
+            source: Any, event: A2AConversationCompletedEvent
+        ) -> None:
+            self._handle_action_event("a2a_conversation_completed", source, event)
+
+        @event_bus.on(A2APollingStartedEvent)
+        def on_a2a_polling_started(source: Any, event: A2APollingStartedEvent) -> None:
+            self._handle_action_event("a2a_polling_started", source, event)
+
+        @event_bus.on(A2APollingStatusEvent)
+        def on_a2a_polling_status(source: Any, event: A2APollingStatusEvent) -> None:
+            self._handle_action_event("a2a_polling_status", source, event)
+
+        @event_bus.on(A2APushNotificationRegisteredEvent)
+        def on_a2a_push_notification_registered(
+            source: Any, event: A2APushNotificationRegisteredEvent
+        ) -> None:
+            self._handle_action_event("a2a_push_notification_registered", source, event)
+
+        @event_bus.on(A2APushNotificationReceivedEvent)
+        def on_a2a_push_notification_received(
+            source: Any, event: A2APushNotificationReceivedEvent
+        ) -> None:
+            self._handle_action_event("a2a_push_notification_received", source, event)
+
+        @event_bus.on(A2APushNotificationSentEvent)
+        def on_a2a_push_notification_sent(
+            source: Any, event: A2APushNotificationSentEvent
+        ) -> None:
+            self._handle_action_event("a2a_push_notification_sent", source, event)
+
+        @event_bus.on(A2APushNotificationTimeoutEvent)
+        def on_a2a_push_notification_timeout(
+            source: Any, event: A2APushNotificationTimeoutEvent
+        ) -> None:
+            self._handle_action_event("a2a_push_notification_timeout", source, event)
+
+        @event_bus.on(A2AStreamingStartedEvent)
+        def on_a2a_streaming_started(
+            source: Any, event: A2AStreamingStartedEvent
+        ) -> None:
+            self._handle_action_event("a2a_streaming_started", source, event)
+
+        @event_bus.on(A2AStreamingChunkEvent)
+        def on_a2a_streaming_chunk(source: Any, event: A2AStreamingChunkEvent) -> None:
+            self._handle_action_event("a2a_streaming_chunk", source, event)
+
+        @event_bus.on(A2AAgentCardFetchedEvent)
+        def on_a2a_agent_card_fetched(
+            source: Any, event: A2AAgentCardFetchedEvent
+        ) -> None:
+            self._handle_action_event("a2a_agent_card_fetched", source, event)
+
+        @event_bus.on(A2AAuthenticationFailedEvent)
+        def on_a2a_authentication_failed(
+            source: Any, event: A2AAuthenticationFailedEvent
+        ) -> None:
+            self._handle_action_event("a2a_authentication_failed", source, event)
+
+        @event_bus.on(A2AArtifactReceivedEvent)
+        def on_a2a_artifact_received(
+            source: Any, event: A2AArtifactReceivedEvent
+        ) -> None:
+            self._handle_action_event("a2a_artifact_received", source, event)
+
+        @event_bus.on(A2AConnectionErrorEvent)
+        def on_a2a_connection_error(
+            source: Any, event: A2AConnectionErrorEvent
+        ) -> None:
+            self._handle_action_event("a2a_connection_error", source, event)
+
+        @event_bus.on(A2AServerTaskStartedEvent)
+        def on_a2a_server_task_started(
+            source: Any, event: A2AServerTaskStartedEvent
+        ) -> None:
+            self._handle_action_event("a2a_server_task_started", source, event)
+
+        @event_bus.on(A2AServerTaskCompletedEvent)
+        def on_a2a_server_task_completed(
+            source: Any, event: A2AServerTaskCompletedEvent
+        ) -> None:
+            self._handle_action_event("a2a_server_task_completed", source, event)
+
+        @event_bus.on(A2AServerTaskCanceledEvent)
+        def on_a2a_server_task_canceled(
+            source: Any, event: A2AServerTaskCanceledEvent
+        ) -> None:
+            self._handle_action_event("a2a_server_task_canceled", source, event)
+
+        @event_bus.on(A2AServerTaskFailedEvent)
+        def on_a2a_server_task_failed(
+            source: Any, event: A2AServerTaskFailedEvent
+        ) -> None:
+            self._handle_action_event("a2a_server_task_failed", source, event)
+
+        @event_bus.on(A2AParallelDelegationStartedEvent)
+        def on_a2a_parallel_delegation_started(
+            source: Any, event: A2AParallelDelegationStartedEvent
+        ) -> None:
+            self._handle_action_event("a2a_parallel_delegation_started", source, event)
+
+        @event_bus.on(A2AParallelDelegationCompletedEvent)
+        def on_a2a_parallel_delegation_completed(
+            source: Any, event: A2AParallelDelegationCompletedEvent
+        ) -> None:
+            self._handle_action_event(
+                "a2a_parallel_delegation_completed", source, event
+            )
+
     def _register_system_event_handlers(self, event_bus: CrewAIEventsBus) -> None:
         """Register handlers for system signal events (SIGTERM, SIGINT, etc.)."""
 
@@ -570,10 +738,15 @@ class TraceCollectionListener(BaseEventListener):
         if event_type not in self.complex_events:
             return safe_serialize_to_dict(event)
         if event_type == "task_started":
+            task_name = event.task.name or event.task.description
+            task_display_name = (
+                task_name[:80] + "..." if len(task_name) > 80 else task_name
+            )
             return {
                 "task_description": event.task.description,
                 "expected_output": event.task.expected_output,
-                "task_name": event.task.name or event.task.description,
+                "task_name": task_name,
+                "task_display_name": task_display_name,
                 "context": event.context,
                 "agent_role": source.agent.role,
                 "task_id": str(event.task.id),

lib/crewai/src/crewai/events/types/a2a_events.py

@@ -4,68 +4,120 @@ This module defines events emitted during A2A protocol delegation,
 including both single-turn and multiturn conversation flows.
 """
 
+from __future__ import annotations
+
 from typing import Any, Literal
 
+from pydantic import model_validator
+
 from crewai.events.base_events import BaseEvent
 
 
 class A2AEventBase(BaseEvent):
     """Base class for A2A events with task/agent context."""
 
-    from_task: Any | None = None
+    from_task: Any = None
-    from_agent: Any | None = None
+    from_agent: Any = None
 
-    def __init__(self, **data: Any) -> None:
+    @model_validator(mode="before")
-        """Initialize A2A event, extracting task and agent metadata."""
+    @classmethod
-        if data.get("from_task"):
+    def extract_task_and_agent_metadata(cls, data: dict[str, Any]) -> dict[str, Any]:
-            task = data["from_task"]
+        """Extract task and agent metadata before validation."""
+        if task := data.get("from_task"):
             data["task_id"] = str(task.id)
             data["task_name"] = task.name or task.description
+            data.setdefault("source_fingerprint", str(task.id))
+            data.setdefault("source_type", "task")
+            data.setdefault(
+                "fingerprint_metadata",
+                {
+                    "task_id": str(task.id),
+                    "task_name": task.name or task.description,
+                },
+            )
             data["from_task"] = None
 
-        if data.get("from_agent"):
+        if agent := data.get("from_agent"):
-            agent = data["from_agent"]
             data["agent_id"] = str(agent.id)
             data["agent_role"] = agent.role
+            data.setdefault("source_fingerprint", str(agent.id))
+            data.setdefault("source_type", "agent")
+            data.setdefault(
+                "fingerprint_metadata",
+                {
+                    "agent_id": str(agent.id),
+                    "agent_role": agent.role,
+                },
+            )
             data["from_agent"] = None
 
-        super().__init__(**data)
+        return data
 
 
 class A2ADelegationStartedEvent(A2AEventBase):
     """Event emitted when A2A delegation starts.
 
     Attributes:
-        endpoint: A2A agent endpoint URL (AgentCard URL)
+        endpoint: A2A agent endpoint URL (AgentCard URL).
-        task_description: Task being delegated to the A2A agent
+        task_description: Task being delegated to the A2A agent.
-        agent_id: A2A agent identifier
+        agent_id: A2A agent identifier.
-        is_multiturn: Whether this is part of a multiturn conversation
+        context_id: A2A context ID grouping related tasks.
-        turn_number: Current turn number (1-indexed, 1 for single-turn)
+        is_multiturn: Whether this is part of a multiturn conversation.
+        turn_number: Current turn number (1-indexed, 1 for single-turn).
+        a2a_agent_name: Name of the A2A agent from agent card.
+        agent_card: Full A2A agent card metadata.
+        protocol_version: A2A protocol version being used.
+        provider: Agent provider/organization info from agent card.
+        skill_id: ID of the specific skill being invoked.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
     """
 
     type: str = "a2a_delegation_started"
     endpoint: str
     task_description: str
     agent_id: str
+    context_id: str | None = None
     is_multiturn: bool = False
     turn_number: int = 1
+    a2a_agent_name: str | None = None
+    agent_card: dict[str, Any] | None = None
+    protocol_version: str | None = None
+    provider: dict[str, Any] | None = None
+    skill_id: str | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
 
 
 class A2ADelegationCompletedEvent(A2AEventBase):
     """Event emitted when A2A delegation completes.
 
     Attributes:
-        status: Completion status (completed, input_required, failed, etc.)
+        status: Completion status (completed, input_required, failed, etc.).
-        result: Result message if status is completed
+        result: Result message if status is completed.
-        error: Error/response message (error for failed, response for input_required)
+        error: Error/response message (error for failed, response for input_required).
-        is_multiturn: Whether this is part of a multiturn conversation
+        context_id: A2A context ID grouping related tasks.
+        is_multiturn: Whether this is part of a multiturn conversation.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        agent_card: Full A2A agent card metadata.
+        provider: Agent provider/organization info from agent card.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
     """
 
     type: str = "a2a_delegation_completed"
     status: str
     result: str | None = None
     error: str | None = None
+    context_id: str | None = None
     is_multiturn: bool = False
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    agent_card: dict[str, Any] | None = None
+    provider: dict[str, Any] | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
 
 
 class A2AConversationStartedEvent(A2AEventBase):
@@ -75,51 +127,95 @@ class A2AConversationStartedEvent(A2AEventBase):
     before the first message exchange.
 
     Attributes:
-        agent_id: A2A agent identifier
+        agent_id: A2A agent identifier.
-        endpoint: A2A agent endpoint URL
+        endpoint: A2A agent endpoint URL.
-        a2a_agent_name: Name of the A2A agent from agent card
+        context_id: A2A context ID grouping related tasks.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        agent_card: Full A2A agent card metadata.
+        protocol_version: A2A protocol version being used.
+        provider: Agent provider/organization info from agent card.
+        skill_id: ID of the specific skill being invoked.
+        reference_task_ids: Related task IDs for context.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
     """
 
     type: str = "a2a_conversation_started"
     agent_id: str
     endpoint: str
+    context_id: str | None = None
     a2a_agent_name: str | None = None
+    agent_card: dict[str, Any] | None = None
+    protocol_version: str | None = None
+    provider: dict[str, Any] | None = None
+    skill_id: str | None = None
+    reference_task_ids: list[str] | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
 
 
 class A2AMessageSentEvent(A2AEventBase):
     """Event emitted when a message is sent to the A2A agent.
 
     Attributes:
-        message: Message content sent to the A2A agent
+        message: Message content sent to the A2A agent.
-        turn_number: Current turn number (1-indexed)
+        turn_number: Current turn number (1-indexed).
-        is_multiturn: Whether this is part of a multiturn conversation
+        context_id: A2A context ID grouping related tasks.
-        agent_role: Role of the CrewAI agent sending the message
+        message_id: Unique A2A message identifier.
+        is_multiturn: Whether this is part of a multiturn conversation.
+        agent_role: Role of the CrewAI agent sending the message.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        skill_id: ID of the specific skill being invoked.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
     """
 
     type: str = "a2a_message_sent"
     message: str
     turn_number: int
+    context_id: str | None = None
+    message_id: str | None = None
     is_multiturn: bool = False
     agent_role: str | None = None
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    skill_id: str | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
 
 
 class A2AResponseReceivedEvent(A2AEventBase):
     """Event emitted when a response is received from the A2A agent.
 
     Attributes:
-        response: Response content from the A2A agent
+        response: Response content from the A2A agent.
-        turn_number: Current turn number (1-indexed)
+        turn_number: Current turn number (1-indexed).
-        is_multiturn: Whether this is part of a multiturn conversation
+        context_id: A2A context ID grouping related tasks.
-        status: Response status (input_required, completed, etc.)
+        message_id: Unique A2A message identifier.
-        agent_role: Role of the CrewAI agent (for display)
+        is_multiturn: Whether this is part of a multiturn conversation.
+        status: Response status (input_required, completed, etc.).
+        final: Whether this is the final response in the stream.
+        agent_role: Role of the CrewAI agent (for display).
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
     """
 
     type: str = "a2a_response_received"
     response: str
     turn_number: int
+    context_id: str | None = None
+    message_id: str | None = None
     is_multiturn: bool = False
     status: str
+    final: bool = False
     agent_role: str | None = None
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
 
 
 class A2AConversationCompletedEvent(A2AEventBase):
@@ -128,119 +224,433 @@ class A2AConversationCompletedEvent(A2AEventBase):
     This is emitted once at the end of a multiturn conversation.
 
     Attributes:
-        status: Final status (completed, failed, etc.)
+        status: Final status (completed, failed, etc.).
-        final_result: Final result if completed successfully
+        final_result: Final result if completed successfully.
-        error: Error message if failed
+        error: Error message if failed.
-        total_turns: Total number of turns in the conversation
+        context_id: A2A context ID grouping related tasks.
+        total_turns: Total number of turns in the conversation.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        agent_card: Full A2A agent card metadata.
+        reference_task_ids: Related task IDs for context.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
     """
 
     type: str = "a2a_conversation_completed"
     status: Literal["completed", "failed"]
     final_result: str | None = None
     error: str | None = None
+    context_id: str | None = None
     total_turns: int
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    agent_card: dict[str, Any] | None = None
+    reference_task_ids: list[str] | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
 
 
 class A2APollingStartedEvent(A2AEventBase):
     """Event emitted when polling mode begins for A2A delegation.
 
     Attributes:
-        task_id: A2A task ID being polled
+        task_id: A2A task ID being polled.
-        polling_interval: Seconds between poll attempts
+        context_id: A2A context ID grouping related tasks.
-        endpoint: A2A agent endpoint URL
+        polling_interval: Seconds between poll attempts.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        metadata: Custom A2A metadata key-value pairs.
     """
 
     type: str = "a2a_polling_started"
     task_id: str
+    context_id: str | None = None
     polling_interval: float
     endpoint: str
+    a2a_agent_name: str | None = None
+    metadata: dict[str, Any] | None = None
 
 
 class A2APollingStatusEvent(A2AEventBase):
     """Event emitted on each polling iteration.
 
     Attributes:
-        task_id: A2A task ID being polled
+        task_id: A2A task ID being polled.
-        state: Current task state from remote agent
+        context_id: A2A context ID grouping related tasks.
-        elapsed_seconds: Time since polling started
+        state: Current task state from remote agent.
-        poll_count: Number of polls completed
+        elapsed_seconds: Time since polling started.
+        poll_count: Number of polls completed.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        metadata: Custom A2A metadata key-value pairs.
     """
 
     type: str = "a2a_polling_status"
     task_id: str
+    context_id: str | None = None
     state: str
     elapsed_seconds: float
     poll_count: int
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    metadata: dict[str, Any] | None = None
 
 
 class A2APushNotificationRegisteredEvent(A2AEventBase):
     """Event emitted when push notification callback is registered.
 
     Attributes:
-        task_id: A2A task ID for which callback is registered
+        task_id: A2A task ID for which callback is registered.
-        callback_url: URL where agent will send push notifications
+        context_id: A2A context ID grouping related tasks.
+        callback_url: URL where agent will send push notifications.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        metadata: Custom A2A metadata key-value pairs.
     """
 
     type: str = "a2a_push_notification_registered"
     task_id: str
+    context_id: str | None = None
     callback_url: str
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    metadata: dict[str, Any] | None = None
 
 
 class A2APushNotificationReceivedEvent(A2AEventBase):
     """Event emitted when a push notification is received.
 
+    This event should be emitted by the user's webhook handler when it receives
+    a push notification from the remote A2A agent, before calling
+    `result_store.store_result()`.
+
     Attributes:
-        task_id: A2A task ID from the notification
+        task_id: A2A task ID from the notification.
-        state: Current task state from the notification
+        context_id: A2A context ID grouping related tasks.
+        state: Current task state from the notification.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        metadata: Custom A2A metadata key-value pairs.
     """
 
     type: str = "a2a_push_notification_received"
     task_id: str
+    context_id: str | None = None
     state: str
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    metadata: dict[str, Any] | None = None
+
+
+class A2APushNotificationSentEvent(A2AEventBase):
+    """Event emitted when a push notification is sent to a callback URL.
+
+    Emitted by the A2A server when it sends a task status update to the
+    client's registered push notification callback URL.
+
+    Attributes:
+        task_id: A2A task ID being notified.
+        context_id: A2A context ID grouping related tasks.
+        callback_url: URL the notification was sent to.
+        state: Task state being reported.
+        success: Whether the notification was successfully delivered.
+        error: Error message if delivery failed.
+        metadata: Custom A2A metadata key-value pairs.
+    """
+
+    type: str = "a2a_push_notification_sent"
+    task_id: str
+    context_id: str | None = None
+    callback_url: str
+    state: str
+    success: bool = True
+    error: str | None = None
+    metadata: dict[str, Any] | None = None
 
 
 class A2APushNotificationTimeoutEvent(A2AEventBase):
     """Event emitted when push notification wait times out.
 
     Attributes:
-        task_id: A2A task ID that timed out
+        task_id: A2A task ID that timed out.
-        timeout_seconds: Timeout duration in seconds
+        context_id: A2A context ID grouping related tasks.
+        timeout_seconds: Timeout duration in seconds.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        metadata: Custom A2A metadata key-value pairs.
     """
 
     type: str = "a2a_push_notification_timeout"
     task_id: str
+    context_id: str | None = None
     timeout_seconds: float
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    metadata: dict[str, Any] | None = None
+
+
+class A2AStreamingStartedEvent(A2AEventBase):
+    """Event emitted when streaming mode begins for A2A delegation.
+
+    Attributes:
+        task_id: A2A task ID for the streaming session.
+        context_id: A2A context ID grouping related tasks.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        turn_number: Current turn number (1-indexed).
+        is_multiturn: Whether this is part of a multiturn conversation.
+        agent_role: Role of the CrewAI agent.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
+    """
+
+    type: str = "a2a_streaming_started"
+    task_id: str | None = None
+    context_id: str | None = None
+    endpoint: str
+    a2a_agent_name: str | None = None
+    turn_number: int = 1
+    is_multiturn: bool = False
+    agent_role: str | None = None
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
+
+
+class A2AStreamingChunkEvent(A2AEventBase):
+    """Event emitted when a streaming chunk is received.
+
+    Attributes:
+        task_id: A2A task ID for the streaming session.
+        context_id: A2A context ID grouping related tasks.
+        chunk: The text content of the chunk.
+        chunk_index: Index of this chunk in the stream (0-indexed).
+        final: Whether this is the final chunk in the stream.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        turn_number: Current turn number (1-indexed).
+        is_multiturn: Whether this is part of a multiturn conversation.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
+    """
+
+    type: str = "a2a_streaming_chunk"
+    task_id: str | None = None
+    context_id: str | None = None
+    chunk: str
+    chunk_index: int
+    final: bool = False
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    turn_number: int = 1
+    is_multiturn: bool = False
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
+
+
+class A2AAgentCardFetchedEvent(A2AEventBase):
+    """Event emitted when an agent card is successfully fetched.
+
+    Attributes:
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        agent_card: Full A2A agent card metadata.
+        protocol_version: A2A protocol version from agent card.
+        provider: Agent provider/organization info from agent card.
+        cached: Whether the agent card was retrieved from cache.
+        fetch_time_ms: Time taken to fetch the agent card in milliseconds.
+        metadata: Custom A2A metadata key-value pairs.
+    """
+
+    type: str = "a2a_agent_card_fetched"
+    endpoint: str
+    a2a_agent_name: str | None = None
+    agent_card: dict[str, Any] | None = None
+    protocol_version: str | None = None
+    provider: dict[str, Any] | None = None
+    cached: bool = False
+    fetch_time_ms: float | None = None
+    metadata: dict[str, Any] | None = None
+
+
+class A2AAuthenticationFailedEvent(A2AEventBase):
+    """Event emitted when authentication to an A2A agent fails.
+
+    Attributes:
+        endpoint: A2A agent endpoint URL.
+        auth_type: Type of authentication attempted (e.g., bearer, oauth2, api_key).
+        error: Error message describing the failure.
+        status_code: HTTP status code if applicable.
+        a2a_agent_name: Name of the A2A agent if known.
+        protocol_version: A2A protocol version being used.
+        metadata: Custom A2A metadata key-value pairs.
+    """
+
+    type: str = "a2a_authentication_failed"
+    endpoint: str
+    auth_type: str | None = None
+    error: str
+    status_code: int | None = None
+    a2a_agent_name: str | None = None
+    protocol_version: str | None = None
+    metadata: dict[str, Any] | None = None
+
+
+class A2AArtifactReceivedEvent(A2AEventBase):
+    """Event emitted when an artifact is received from a remote A2A agent.
+
+    Attributes:
+        task_id: A2A task ID the artifact belongs to.
+        artifact_id: Unique identifier for the artifact.
+        artifact_name: Name of the artifact.
+        artifact_description: Purpose description of the artifact.
+        mime_type: MIME type of the artifact content.
+        size_bytes: Size of the artifact in bytes.
+        append: Whether content should be appended to existing artifact.
+        last_chunk: Whether this is the final chunk of the artifact.
+        endpoint: A2A agent endpoint URL.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        context_id: Context ID for correlation.
+        turn_number: Current turn number (1-indexed).
+        is_multiturn: Whether this is part of a multiturn conversation.
+        metadata: Custom A2A metadata key-value pairs.
+        extensions: List of A2A extension URIs in use.
+    """
+
+    type: str = "a2a_artifact_received"
+    task_id: str
+    artifact_id: str
+    artifact_name: str | None = None
+    artifact_description: str | None = None
+    mime_type: str | None = None
+    size_bytes: int | None = None
+    append: bool = False
+    last_chunk: bool = False
+    endpoint: str | None = None
+    a2a_agent_name: str | None = None
+    context_id: str | None = None
+    turn_number: int = 1
+    is_multiturn: bool = False
+    metadata: dict[str, Any] | None = None
+    extensions: list[str] | None = None
+
+
+class A2AConnectionErrorEvent(A2AEventBase):
+    """Event emitted when a connection error occurs during A2A communication.
+
+    Attributes:
+        endpoint: A2A agent endpoint URL.
+        error: Error message describing the connection failure.
+        error_type: Type of error (e.g., timeout, connection_refused, dns_error).
+        status_code: HTTP status code if applicable.
+        a2a_agent_name: Name of the A2A agent from agent card.
+        operation: The operation being attempted when error occurred.
+        context_id: A2A context ID grouping related tasks.
+        task_id: A2A task ID if applicable.
+        metadata: Custom A2A metadata key-value pairs.
+    """
+
+    type: str = "a2a_connection_error"
+    endpoint: str
+    error: str
+    error_type: str | None = None
+    status_code: int | None = None
+    a2a_agent_name: str | None = None
+    operation: str | None = None
+    context_id: str | None = None
+    task_id: str | None = None
+    metadata: dict[str, Any] | None = None
 
 
 class A2AServerTaskStartedEvent(A2AEventBase):
-    """Event emitted when an A2A server task execution starts."""
+    """Event emitted when an A2A server task execution starts.
+
+    Attributes:
+        task_id: A2A task ID for this execution.
+        context_id: A2A context ID grouping related tasks.
+        metadata: Custom A2A metadata key-value pairs.
+    """
 
     type: str = "a2a_server_task_started"
-    a2a_task_id: str
+    task_id: str
-    a2a_context_id: str
+    context_id: str
+    metadata: dict[str, Any] | None = None
 
 
 class A2AServerTaskCompletedEvent(A2AEventBase):
-    """Event emitted when an A2A server task execution completes."""
+    """Event emitted when an A2A server task execution completes.
+
+    Attributes:
+        task_id: A2A task ID for this execution.
+        context_id: A2A context ID grouping related tasks.
+        result: The task result.
+        metadata: Custom A2A metadata key-value pairs.
+    """
 
     type: str = "a2a_server_task_completed"
-    a2a_task_id: str
+    task_id: str
-    a2a_context_id: str
+    context_id: str
     result: str
+    metadata: dict[str, Any] | None = None
 
 
 class A2AServerTaskCanceledEvent(A2AEventBase):
-    """Event emitted when an A2A server task execution is canceled."""
+    """Event emitted when an A2A server task execution is canceled.
+
+    Attributes:
+        task_id: A2A task ID for this execution.
+        context_id: A2A context ID grouping related tasks.
+        metadata: Custom A2A metadata key-value pairs.
+    """
 
     type: str = "a2a_server_task_canceled"
-    a2a_task_id: str
+    task_id: str
-    a2a_context_id: str
+    context_id: str
+    metadata: dict[str, Any] | None = None
 
 
 class A2AServerTaskFailedEvent(A2AEventBase):
-    """Event emitted when an A2A server task execution fails."""
+    """Event emitted when an A2A server task execution fails.
+
+    Attributes:
+        task_id: A2A task ID for this execution.
+        context_id: A2A context ID grouping related tasks.
+        error: Error message describing the failure.
+        metadata: Custom A2A metadata key-value pairs.
+    """
 
     type: str = "a2a_server_task_failed"
-    a2a_task_id: str
+    task_id: str
-    a2a_context_id: str
+    context_id: str
     error: str
+    metadata: dict[str, Any] | None = None
+
+
+class A2AParallelDelegationStartedEvent(A2AEventBase):
+    """Event emitted when parallel delegation to multiple A2A agents begins.
+
+    Attributes:
+        endpoints: List of A2A agent endpoints being delegated to.
+        task_description: Description of the task being delegated.
+    """
+
+    type: str = "a2a_parallel_delegation_started"
+    endpoints: list[str]
+    task_description: str
+
+
+class A2AParallelDelegationCompletedEvent(A2AEventBase):
+    """Event emitted when parallel delegation to multiple A2A agents completes.
+
+    Attributes:
+        endpoints: List of A2A agent endpoints that were delegated to.
+        success_count: Number of successful delegations.
+        failure_count: Number of failed delegations.
+        results: Summary of results from each agent.
+    """
+
+    type: str = "a2a_parallel_delegation_completed"
+    endpoints: list[str]
+    success_count: int
+    failure_count: int
+    results: dict[str, str] | None = None

lib/crewai/tests/a2a/utils/test_task.py

@@ -26,9 +26,13 @@ def mock_agent() -> MagicMock:
 
 
 @pytest.fixture
-def mock_task() -> MagicMock:
+def mock_task(mock_context: MagicMock) -> MagicMock:
     """Create a mock Task."""
-    return MagicMock()
+    task = MagicMock()
+    task.id = mock_context.task_id
+    task.name = "Mock Task"
+    task.description = "Mock task description"
+    return task
 
 
 @pytest.fixture
@@ -179,8 +183,8 @@ class TestExecute:
         event = first_call[0][1]
 
         assert event.type == "a2a_server_task_started"
-        assert event.a2a_task_id == mock_context.task_id
+        assert event.task_id == mock_context.task_id
-        assert event.a2a_context_id == mock_context.context_id
+        assert event.context_id == mock_context.context_id
 
     @pytest.mark.asyncio
     async def test_emits_completed_event(
@@ -201,7 +205,7 @@ class TestExecute:
         event = second_call[0][1]
 
         assert event.type == "a2a_server_task_completed"
-        assert event.a2a_task_id == mock_context.task_id
+        assert event.task_id == mock_context.task_id
         assert event.result == "Task completed successfully"
 
     @pytest.mark.asyncio
@@ -250,7 +254,7 @@ class TestExecute:
         event = canceled_call[0][1]
 
         assert event.type == "a2a_server_task_canceled"
-        assert event.a2a_task_id == mock_context.task_id
+        assert event.task_id == mock_context.task_id
 
 
 class TestCancel:

lib/crewai/tests/agents/test_a2a_trust_completion_status.py

@@ -14,6 +14,16 @@ except ImportError:
     A2A_SDK_INSTALLED = False
 
 
+def _create_mock_agent_card(name: str = "Test", url: str = "http://test-endpoint.com/"):
+    """Create a mock agent card with proper model_dump behavior."""
+    mock_card = MagicMock()
+    mock_card.name = name
+    mock_card.url = url
+    mock_card.model_dump.return_value = {"name": name, "url": url}
+    mock_card.model_dump_json.return_value = f'{{"name": "{name}", "url": "{url}"}}'
+    return mock_card
+
+
 @pytest.mark.skipif(not A2A_SDK_INSTALLED, reason="Requires a2a-sdk to be installed")
 def test_trust_remote_completion_status_true_returns_directly():
     """When trust_remote_completion_status=True and A2A returns completed, return result directly."""
@@ -44,8 +54,7 @@ def test_trust_remote_completion_status_true_returns_directly():
         patch("crewai.a2a.wrapper.execute_a2a_delegation") as mock_execute,
         patch("crewai.a2a.wrapper._fetch_agent_cards_concurrently") as mock_fetch,
     ):
-        mock_card = MagicMock()
+        mock_card = _create_mock_agent_card()
-        mock_card.name = "Test"
         mock_fetch.return_value = ({"http://test-endpoint.com/": mock_card}, {})
 
         # A2A returns completed
@@ -110,8 +119,7 @@ def test_trust_remote_completion_status_false_continues_conversation():
         patch("crewai.a2a.wrapper.execute_a2a_delegation") as mock_execute,
         patch("crewai.a2a.wrapper._fetch_agent_cards_concurrently") as mock_fetch,
     ):
-        mock_card = MagicMock()
+        mock_card = _create_mock_agent_card()
-        mock_card.name = "Test"
         mock_fetch.return_value = ({"http://test-endpoint.com/": mock_card}, {})
 
         # A2A returns completed