refactor(server): remove ServerError wrapper

Re #737

Author: ishymko

src/a2a/server/agent_execution/context.py

@@ -13,7 +13,7 @@
     Task,
 )
 from a2a.utils import get_message_text
-from a2a.utils.errors import InvalidParamsError, ServerError
+from a2a.utils.errors import InvalidParamsError
 
 
 class RequestContext:
@@ -67,15 +67,13 @@ def __init__(  # noqa: PLR0913
             if task_id:
                 self._params.message.task_id = task_id
                 if task and task.id != task_id:
-                    raise ServerError(InvalidParamsError(message='bad task id'))
+                    raise InvalidParamsError(message='bad task id')
             else:
                 self._check_or_generate_task_id()
             if context_id:
                 self._params.message.context_id = context_id
                 if task and task.context_id != context_id:
-                    raise ServerError(
-                        InvalidParamsError(message='bad context id')
-                    )
+                    raise InvalidParamsError(message='bad context id')
             else:
                 self._check_or_generate_context_id()
 

src/a2a/server/apps/rest/rest_adapter.py

@@ -46,7 +46,6 @@
 from a2a.utils.errors import (
     AuthenticatedExtendedCardNotConfiguredError,
     InvalidRequestError,
-    ServerError,
 )
 
 
@@ -127,10 +126,8 @@ async def _handle_streaming_request(
         try:
             await request.body()
         except (ValueError, RuntimeError, OSError) as e:
-            raise ServerError(
-                error=InvalidRequestError(
-                    message=f'Failed to pre-consume request body: {e}'
-                )
+            raise InvalidRequestError(
+                message=f'Failed to pre-consume request body: {e}'
             ) from e
 
         call_context = self._context_builder.build(request)
@@ -179,10 +176,8 @@ async def handle_authenticated_agent_card(
             A JSONResponse containing the authenticated card.
         """
         if not self.agent_card.capabilities.extended_agent_card:
-            raise ServerError(
-                error=AuthenticatedExtendedCardNotConfiguredError(
-                    message='Authenticated card not supported'
-                )
+            raise AuthenticatedExtendedCardNotConfiguredError(
+                message='Authenticated card not supported'
             )
         card_to_serve = self.extended_agent_card
 

src/a2a/server/events/event_consumer.py

@@ -13,7 +13,7 @@
     TaskState,
     TaskStatusUpdateEvent,
 )
-from a2a.utils.errors import InternalError, ServerError
+from a2a.utils.errors import InternalError
 from a2a.utils.telemetry import SpanKind, trace_class
 
 
@@ -49,16 +49,16 @@ async def consume_one(self) -> Event:
             The next event from the queue.
 
         Raises:
-            ServerError: If the queue is empty when attempting to dequeue
+            InternalError: If the queue is empty when attempting to dequeue
                 immediately.
         """
         logger.debug('Attempting to consume one event.')
         try:
             event = await self.queue.dequeue_event(no_wait=True)
         except asyncio.QueueEmpty as e:
             logger.warning('Event queue was empty in consume_one.')
-            raise ServerError(
-                InternalError(message='Agent did not return any response')
+            raise InternalError(
+                message='Agent did not return any response'
             ) from e
 
         logger.debug('Dequeued event of type: %s in consume_one.', type(event))

src/a2a/server/request_handlers/default_request_handler.py

@@ -48,7 +48,6 @@
 from a2a.utils.errors import (
     InternalError,
     InvalidParamsError,
-    ServerError,
     TaskNotCancelableError,
     TaskNotFoundError,
     UnsupportedOperationError,
@@ -132,7 +131,7 @@ async def on_get_task(
         task_id = params.id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         return apply_history_length(task, params)
 
@@ -169,14 +168,12 @@ async def on_cancel_task(
         task_id = params.id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         # Check if task is in a non-cancelable state (completed, canceled, failed, rejected)
         if task.status.state in TERMINAL_TASK_STATES:
-            raise ServerError(
-                error=TaskNotCancelableError(
-                    message=f'Task cannot be canceled - current state: {task.status.state}'
-                )
+            raise TaskNotCancelableError(
+                message=f'Task cannot be canceled - current state: {task.status.state}'
             )
 
         task_manager = TaskManager(
@@ -208,17 +205,13 @@ async def on_cancel_task(
         consumer = EventConsumer(queue)
         result = await result_aggregator.consume_all(consumer)
         if not isinstance(result, Task):
-            raise ServerError(
-                error=InternalError(
-                    message='Agent did not return valid response for cancel'
-                )
+            raise InternalError(
+                message='Agent did not return valid response for cancel'
             )
 
         if result.status.state != TaskState.TASK_STATE_CANCELED:
-            raise ServerError(
-                error=TaskNotCancelableError(
-                    message=f'Task cannot be canceled - current state: {result.status.state}'
-                )
+            raise TaskNotCancelableError(
+                message=f'Task cannot be canceled - current state: {result.status.state}'
             )
 
         return result
@@ -260,18 +253,14 @@ async def _setup_message_execution(
 
         if task:
             if task.status.state in TERMINAL_TASK_STATES:
-                raise ServerError(
-                    error=InvalidParamsError(
-                        message=f'Task {task.id} is in terminal state: {task.status.state}'
-                    )
+                raise InvalidParamsError(
+                    message=f'Task {task.id} is in terminal state: {task.status.state}'
                 )
 
             task = task_manager.update_with_message(params.message, task)
         elif params.message.task_id:
-            raise ServerError(
-                error=TaskNotFoundError(
-                    message=f'Task {params.message.task_id} was specified but does not exist'
-                )
+            raise TaskNotFoundError(
+                message=f'Task {params.message.task_id} was specified but does not exist'
             )
 
         # Build request context
@@ -317,9 +306,7 @@ def _validate_task_id_match(self, task_id: str, event_task_id: str) -> None:
                 event_task_id,
                 task_id,
             )
-            raise ServerError(
-                InternalError(message='Task ID mismatch in agent response')
-            )
+            raise InternalError(message='Task ID mismatch in agent response')
 
     async def _send_push_notification_if_needed(
         self, task_id: str, event: Event
@@ -389,7 +376,7 @@ async def push_notification_callback(event: Event) -> None:
                 await self._cleanup_producer(producer_task, task_id)
 
         if not result:
-            raise ServerError(error=InternalError())
+            raise InternalError
 
         if isinstance(result, Task):
             self._validate_task_id_match(task_id, result.id)
@@ -496,12 +483,12 @@ async def on_create_task_push_notification_config(
         Requires a `PushNotifier` to be configured.
         """
         if not self._push_config_store:
-            raise ServerError(error=UnsupportedOperationError())
+            raise UnsupportedOperationError
 
         task_id = params.task_id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         await self._push_config_store.set_info(
             task_id,
@@ -524,13 +511,13 @@ async def on_get_task_push_notification_config(
         Requires a `PushConfigStore` to be configured.
         """
         if not self._push_config_store:
-            raise ServerError(error=UnsupportedOperationError())
+            raise UnsupportedOperationError
 
         task_id = params.task_id
         config_id = params.id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         push_notification_configs: list[PushNotificationConfig] = (
             await self._push_config_store.get_info(
@@ -546,9 +533,7 @@ async def on_get_task_push_notification_config(
                     push_notification_config=config,
                 )
 
-        raise ServerError(
-            error=InternalError(message='Push notification config not found')
-        )
+        raise InternalError(message='Push notification config not found')
 
     async def on_subscribe_to_task(
         self,
@@ -563,13 +548,11 @@ async def on_subscribe_to_task(
         task_id = params.id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         if task.status.state in TERMINAL_TASK_STATES:
-            raise ServerError(
-                error=UnsupportedOperationError(
-                    message=f'Task {task.id} is in terminal state: {task.status.state}'
-                )
+            raise UnsupportedOperationError(
+                message=f'Task {task.id} is in terminal state: {task.status.state}'
             )
 
         # The operation MUST return a Task object as the first event in the stream
@@ -588,7 +571,7 @@ async def on_subscribe_to_task(
 
         queue = await self._queue_manager.tap(task.id)
         if not queue:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         consumer = EventConsumer(queue)
         async for event in result_aggregator.consume_and_emit(consumer):
@@ -604,12 +587,12 @@ async def on_list_task_push_notification_configs(
         Requires a `PushConfigStore` to be configured.
         """
         if not self._push_config_store:
-            raise ServerError(error=UnsupportedOperationError())
+            raise UnsupportedOperationError
 
         task_id = params.task_id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         push_notification_config_list = await self._push_config_store.get_info(
             task_id, context or ServerCallContext()
@@ -635,13 +618,13 @@ async def on_delete_task_push_notification_config(
         Requires a `PushConfigStore` to be configured.
         """
         if not self._push_config_store:
-            raise ServerError(error=UnsupportedOperationError())
+            raise UnsupportedOperationError
 
         task_id = params.task_id
         config_id = params.id
         task: Task | None = await self.task_store.get(task_id, context)
         if not task:
-            raise ServerError(error=TaskNotFoundError())
+            raise TaskNotFoundError
 
         await self._push_config_store.delete_info(
             task_id, context or ServerCallContext(), config_id