diff --git a/tests/test_agent.py b/tests/test_agent.py
index cb199e9..f644d22 100644
--- a/tests/test_agent.py
+++ b/tests/test_agent.py
@@ -176,5 +176,5 @@ async def test_end_to_end_deterministic_crashing_image_scenario(ctx, workspace):
     assert verification["recovered"] is False  # no user-visible check supplied
 
     postmortem = await agent.generate_postmortem(ctx, "checkout-001")
-    assert postmortem.incident_id == "checkout-001"
+    assert postmortem["incident_id"] == "checkout-001"
     assert workspace.exists("outputs/incidents/checkout-001/postmortem.json")