[eric] agents: drop spurious @staticmethod on invoke_agent (every InvokeAgent call 500'd)

backend/apps/agents/manager/AgentLaunch.py

@@ -1,4 +1,4 @@
-"""Agent run entry points for AgentManager: launch a new top-level run and the staticmethod
+"""Agent run entry points for AgentManager: launch a new top-level run and the
 invoke_agent helper (fork-and-send a sub-agent). The no-SDK mock fallback lives in MockAgent.
 Split into a mixin to keep the manager file under the size ceiling; self.run_agent_loop /
 self.sessions resolve across the MRO exactly as before."""
@@ -137,7 +137,6 @@ class AgentLaunch(AgentManagerProtocol):
 
         return session
 
-    @staticmethod
     @typechecked
     async def invoke_agent(
         self,

backend/tests/test_invoke_agent.py

@@ -0,0 +1,31 @@
+"""InvokeAgent (agent-to-agent) binding invariant.
+
+The bug: invoke_agent carried a spurious @staticmethod on a def whose first
+parameter is self, so the instance never bound and EVERY call raised
+TypeError("missing 1 required positional argument: 'self'"), which
+/api/invoke-agent/run surfaced as a 500 to the calling agent.
+
+The seal: call it exactly the way the route does (instance, all-keyword args)
+and pin that it reaches the method body: an unknown session must raise the
+body's ValueError, never a binding TypeError.
+"""
+
+import asyncio
+
+import pytest
+
+import backend.apps.agents.manager.AgentLaunch as agent_launch_module
+from backend.apps.agents.agent_manager import agent_manager
+
+
+def test_invoke_agent_binds_as_instance_method(monkeypatch) -> None:
+    monkeypatch.setattr(agent_launch_module, "load_session_data", lambda sid: None)
+
+    async def run() -> None:
+        with pytest.raises(ValueError, match="not found"):
+            await agent_manager.invoke_agent(
+                source_session_id="no-such-session",
+                message="what did you do?",
+            )
+
+    asyncio.run(run())