diff --git a/guard_logs.jsonl b/guard_logs.jsonl
index 3e7fcbc..a9e763e 100644
--- a/guard_logs.jsonl
+++ b/guard_logs.jsonl
@@ -7,3 +7,4 @@
 {"contract_id": "guard-001", "plan": {"action": "move", "costs": {"time": 2.0}, "speed": 0.8}, "state": {"speed": 0.8, "distance_to_obstacle": 5}, "decision": "allow"}
 {"contract_id": "guard-001", "plan": {"action": "move", "costs": {"time": 2.0}, "speed": 0.8}, "state": {"speed": 0.8, "distance_to_obstacle": 5}, "decision": "allow"}
 {"contract_id": "guard-001", "plan": {"action": "move", "costs": {"time": 2.0}, "speed": 0.8}, "state": {"speed": 0.8, "distance_to_obstacle": 5}, "decision": "allow"}
+{"contract_id": "guard-001", "plan": {"action": "move", "costs": {"time": 2.0}, "speed": 0.8}, "state": {"speed": 0.8, "distance_to_obstacle": 5}, "decision": "allow"}
diff --git a/src/guardrail_space/contract.py b/src/guardrail_space/contract.py
index 3d5f6c3..30ccbdb 100644
--- a/src/guardrail_space/contract.py
+++ b/src/guardrail_space/contract.py
@@ -56,11 +56,14 @@ class SafetyContract:
     def evaluate_pre(self, context: Dict[str, Any]) -> (bool, str):
         engine = PolicyEngine(self)
         # Pass a neutral action payload; tests use only context.
-        return engine.evaluate_pre({"action": None}, context)
+        ok, _reason = engine.evaluate_pre({"action": None}, context)
+        # Legacy API expected a boolean result.
+        return bool(ok)
 
     def evaluate_post(self, action: Dict[str, Any], context: Dict[str, Any]) -> (bool, str):
         engine = PolicyEngine(self)
-        return engine.evaluate_post(action, context)
+        ok, _reason = engine.evaluate_post(action, context)
+        return bool(ok)
 
     def to_dict(self) -> Dict[str, Any]:
         return {