refactor(events): standardize handler typing across event buses

Make event subscription signatures explicit and reusable so outbound/inbound bus implementations and agent adapter wiring share one typed contract. This reduces annotation drift and keeps bus integration safer as event layers evolve.

Author: aliev

agents-core/vision_agents/core/agents/agents.py

@@ -3,7 +3,6 @@
 import logging
 import time
 import uuid
-from collections.abc import Awaitable, Callable
 from contextlib import asynccontextmanager, contextmanager
 from pathlib import Path
 from typing import (
@@ -33,7 +32,7 @@
 )
 from ..edge.types import Connection, Participant, TrackType, User
 from ..events import AgentConnectionEvent, EdgeCustomEventOutboundAdapter
-from ..events.bus import EventBus, InMemoryEventBus
+from ..events.bus import EventBus, EventHandler, InMemoryEventBus
 from ..events.manager import EventManager
 from ..instructions import Instructions
 from ..llm import events as llm_events
@@ -1541,7 +1540,7 @@ def _register_default_outbound_adapter_if_needed(self) -> None:
 
     def _resolve_adapter_deliver(
         self, adapter: OutboundEventAdapter
-    ) -> Callable[[AgentConnectionEvent], Awaitable[None]]:
+    ) -> EventHandler[AgentConnectionEvent]:
         deliver = getattr(adapter, "deliver", None)
         if deliver is None:
             raise ValueError(

agents-core/vision_agents/core/events/__init__.py

@@ -7,7 +7,7 @@
     VideoProcessorDetectionEvent,
 )
 from .adapters import EdgeCustomEventOutboundAdapter
-from .bus import EventBus, InMemoryEventBus
+from .bus import EventBus, EventHandler, InMemoryEventBus
 from .manager import EventManager
 
 __all__ = [
@@ -17,6 +17,7 @@
     "ConnectionState",
     "EdgeCustomEventOutboundAdapter",
     "EventBus",
+    "EventHandler",
     "EventManager",
     "InMemoryEventBus",
     "PluginBaseEvent",

agents-core/vision_agents/core/events/bus.py

@@ -1,22 +1,24 @@
 import asyncio
+import inspect
 from collections.abc import Awaitable, Callable
 from typing import Generic, Protocol, TypeVar
 
 T = TypeVar("T")
+EventHandler = Callable[[T], Awaitable[None]]
 
 
 class EventBus(Protocol[T]):
-    def subscribe(self, handler: Callable[[T], Awaitable[None]]) -> None: ...
+    def subscribe(self, handler: EventHandler[T]) -> None: ...
 
     async def publish(self, event: T) -> None: ...
 
 
 class InMemoryEventBus(Generic[T]):
     def __init__(self) -> None:
-        self._handlers: list[Callable[[T], Awaitable[None]]] = []
+        self._handlers: list[EventHandler[T]] = []
 
-    def subscribe(self, handler: Callable[[T], Awaitable[None]]) -> None:
-        if not asyncio.iscoroutinefunction(handler):
+    def subscribe(self, handler: EventHandler[T]) -> None:
+        if not inspect.iscoroutinefunction(handler):
             raise RuntimeError(
                 "Handlers must be coroutines. Use async def handler(event):"
             )