diff --git a/src/strands_compose/hooks/event_publisher.py b/src/strands_compose/hooks/event_publisher.py
index 3b3aa11..13223d6 100644
--- a/src/strands_compose/hooks/event_publisher.py
+++ b/src/strands_compose/hooks/event_publisher.py
@@ -281,14 +281,13 @@ def _on_model_error(self, event: AfterModelCallEvent) -> None:
             return
 
         self._errored = True
-        exc = event.exception
         self._callback(
             StreamEvent(
                 type=EventType.ERROR,
                 agent_name=self._agent_name,
                 data={
-                    "message": f"{type(exc).__name__}: {exc}",
-                    "exception_type": type(exc).__name__,
+                    "text": f"{event.exception}",
+                    "exception_type": type(event.exception).__name__,
                 },
             ),
         )
diff --git a/tests/unit/hooks/test_event_publisher.py b/tests/unit/hooks/test_event_publisher.py
index c73dd34..771061e 100644
--- a/tests/unit/hooks/test_event_publisher.py
+++ b/tests/unit/hooks/test_event_publisher.py
@@ -246,7 +246,7 @@ def test_model_error_emits_error_event(self) -> None:
         assert len(events) == 1
         assert events[0].type == EventType.ERROR
         assert events[0].agent_name == "test"
-        assert "Token has expired" in events[0].data["message"]
+        assert "Token has expired" in events[0].data["text"]
         assert events[0].data["exception_type"] == "RuntimeError"
 
     def test_model_error_sets_errored_flag(self) -> None:
diff --git a/tests/unit/test_golden_outputs.py b/tests/unit/test_golden_outputs.py
index 091a25a..0a6098d 100644
--- a/tests/unit/test_golden_outputs.py
+++ b/tests/unit/test_golden_outputs.py
@@ -209,7 +209,7 @@ def test_model_error_produces_correct_sequence(self) -> None:
         assert len(events) == 2
         assert events[0].type == EventType.AGENT_START
         assert events[1].type == EventType.ERROR
-        assert "Credentials expired" in events[1].data["message"]
+        assert "Credentials expired" in events[1].data["text"]
 
 
 # ---------------------------------------------------------------------------