Only pass conv history to those that need it

Author: steven10a

src/guardrails/agents.py

@@ -191,11 +191,12 @@ class ConversationContextWrapper:
 
         def __init__(self, base: Any, history: list) -> None:
             self._base = base
-            self._conversation_history = history
+            # Expose conversation_history as public attribute per GuardrailLLMContextProto
+            self.conversation_history = history
 
         def get_conversation_history(self) -> list:
             """Return conversation history for conversation-aware guardrails."""
-            return self._conversation_history
+            return self.conversation_history
 
         def __getattr__(self, name: str) -> Any:
             """Delegate all other attribute access to the base context."""

src/guardrails/client.py

@@ -770,8 +770,16 @@ def _run_stage_guardrails(
 
             async def _run_async():
                 ctx = self.context
+
+                # Only wrap context with conversation history if any guardrail in this stage needs it
                 if conversation_history:
-                    ctx = self._create_context_with_conversation(conversation_history)
+                    needs_conversation = any(
+                        getattr(g.definition, "metadata", None)
+                        and g.definition.metadata.uses_conversation_history
+                        for g in self.guardrails[stage_name]
+                    )
+                    if needs_conversation:
+                        ctx = self._create_context_with_conversation(conversation_history)
 
                 results = await run_guardrails(
                     ctx=ctx,

tests/unit/test_agents.py

@@ -1095,7 +1095,10 @@ async def fake_run_guardrails(**kwargs: Any) -> list[GuardrailResult]:
     # Verify the context has the get_conversation_history method
     assert hasattr(captured_context, "get_conversation_history")  # noqa: S101
 
-    # Verify conversation history is present
+    # Verify conversation_history is accessible as an attribute (per GuardrailLLMContextProto)
+    assert hasattr(captured_context, "conversation_history")  # noqa: S101
+
+    # Verify conversation history is present via method
     conversation_history = captured_context.get_conversation_history()
     assert len(conversation_history) == 3  # noqa: S101
     assert conversation_history[0]["role"] == "user"  # noqa: S101
@@ -1104,6 +1107,9 @@ async def fake_run_guardrails(**kwargs: Any) -> list[GuardrailResult]:
     assert conversation_history[2]["role"] == "user"  # noqa: S101
     assert conversation_history[2]["content"] == "Thanks!"  # noqa: S101
 
+    # Verify conversation history is also accessible via direct attribute access
+    assert captured_context.conversation_history == conversation_history  # noqa: S101
+
 
 @pytest.mark.asyncio
 async def test_agent_guardrail_with_empty_conversation_history(monkeypatch: pytest.MonkeyPatch) -> None:
@@ -1142,10 +1148,16 @@ async def fake_run_guardrails(**kwargs: Any) -> list[GuardrailResult]:
     # Verify the context has the get_conversation_history method
     assert hasattr(captured_context, "get_conversation_history")  # noqa: S101
 
-    # Verify conversation history is empty but accessible
+    # Verify conversation_history is accessible as an attribute (per GuardrailLLMContextProto)
+    assert hasattr(captured_context, "conversation_history")  # noqa: S101
+
+    # Verify conversation history is empty but accessible via method
     conversation_history = captured_context.get_conversation_history()
     assert conversation_history == []  # noqa: S101
 
+    # Verify conversation history is also accessible via direct attribute access
+    assert captured_context.conversation_history == []  # noqa: S101
+
 
 # =============================================================================
 # Tests for updated tool-level guardrail behavior (stage_name)