refactor(v2): remove redundant agent protocol

Author: PsiACE

docs/experimental-v2.md

@@ -54,8 +54,8 @@ router = AgentProtocolRouter(
 await router.run()
 ```
 
-The factories create a fresh agent for each connection, so connection state is
-never shared accidentally.
+The selected factory is called once per connection. Return a fresh agent from
+each call to avoid sharing connection state.
 
 Extension method names are explicit and must include the protocol-required `_`
 prefix:

src/acp/experimental/negotiation.py

@@ -24,7 +24,7 @@
 ]
 
 V1AgentFactory = Callable[[V1AgentSideConnection], V1Agent]
-V2AgentFactory = Callable[[V2AgentSideConnection], v2.Agent]
+V2AgentFactory = Callable[[V2AgentSideConnection], object]
 
 
 def _dump(model: BaseModel) -> dict[str, Any]:

src/acp/experimental/v2/__init__.py

@@ -3,12 +3,10 @@
 from . import schema
 from .agent import AgentSideConnection, run_agent
 from .client import ClientSideConnection, connect_to_agent
-from .interfaces import Agent
 from .meta import PROTOCOL_VERSION
 
 __all__ = [
     "PROTOCOL_VERSION",
-    "Agent",
     "AgentSideConnection",
     "ClientSideConnection",
     "connect_to_agent",

src/acp/experimental/v2/agent.py

@@ -19,7 +19,6 @@
     CreateElicitationResponse,
 )
 from ._router import MethodRouter
-from .interfaces import Agent
 from .meta import CLIENT_METHODS
 
 __all__ = ["AgentSideConnection", "run_agent"]
@@ -30,7 +29,7 @@ def _dump(model: BaseModel) -> dict[str, Any]:
 
 
 class _AgentRouter:
-    def __init__(self, agent: Agent, state: InitializationState) -> None:
+    def __init__(self, agent: object, state: InitializationState) -> None:
         self._router = MethodRouter(agent, AGENT_REQUESTS, AGENT_NOTIFICATIONS)
         self._state = state
 
@@ -56,7 +55,7 @@ class AgentSideConnection:
 
     def __init__(
         self,
-        agent: Agent,
+        agent: object,
         input_stream: Any,
         output_stream: Any = None,
         *,
@@ -78,7 +77,7 @@ def __init__(
     @classmethod
     def _attach(
         cls,
-        agent_factory: Callable[[AgentSideConnection], Agent],
+        agent_factory: Callable[[AgentSideConnection], object],
         connection: Connection,
     ) -> tuple[AgentSideConnection, _AgentRouter]:
         self = cls.__new__(cls)
@@ -161,7 +160,7 @@ def _extension_method(method: str) -> str:
 
 
 async def run_agent(
-    agent: Agent,
+    agent: object,
     input_stream: Any = None,
     output_stream: Any = None,
     *,

src/acp/experimental/v2/interfaces.py

@@ -231,7 +231,6 @@ def test_v2_public_entry_point_is_explicit() -> None:
     assert exported["PROTOCOL_VERSION"] == 2
     assert exported["schema"] is v2.schema
     assert set(exported) == {
-        "Agent",
         "AgentSideConnection",
         "ClientSideConnection",
         "PROTOCOL_VERSION",