diff --git a/marimo/_tracer.py b/marimo/_tracer.py
index a518a60daaa..941a460817f 100644
--- a/marimo/_tracer.py
+++ b/marimo/_tracer.py
@@ -250,7 +250,9 @@ def _instrument_ai(provider: trace.TracerProvider) -> None:
         from pydantic_ai import Agent
         from pydantic_ai.models.instrumented import InstrumentationSettings
 
-        Agent.instrument_all(InstrumentationSettings(tracer_provider=provider))
+        Agent.instrument_all(
+            InstrumentationSettings(tracer_provider=provider, version=5)
+        )
         LOGGER.debug("Enabled AI instrumentation")
     except Exception as e:
         LOGGER.debug("AI instrumentation failed: %s", e)
diff --git a/tests/test_tracer.py b/tests/test_tracer.py
index 759cc1c89fa..b0a84058930 100644
--- a/tests/test_tracer.py
+++ b/tests/test_tracer.py
@@ -426,9 +426,21 @@ def test_instruments_when_pydantic_ai_installed(
         from pydantic_ai.models.instrumented import InstrumentationSettings
 
         provider = MagicMock()
-        with patch("pydantic_ai.Agent.instrument_all") as mock_instrument:
+        with (
+            patch("pydantic_ai.Agent.instrument_all") as mock_instrument,
+            patch(
+                "pydantic_ai.models.instrumented.InstrumentationSettings",
+                wraps=InstrumentationSettings,
+            ) as mock_settings,
+        ):
             _instrument_ai(provider)
 
+        # Verify version 5 is passed explicitly instead of relying on newer
+        # Pydantic-AI defaults.
+        mock_settings.assert_called_once_with(
+            tracer_provider=provider,
+            version=5,
+        )
         mock_instrument.assert_called_once()
         settings = mock_instrument.call_args.args[0]
         assert isinstance(settings, InstrumentationSettings)