diff --git a/pyproject.toml b/pyproject.toml
index 326a1fee8..4c8afad4f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "truss"
-version = "0.7.23rc2"
+version = "0.7.23rc3"
 description = "A seamless bridge from model development to model delivery"
 license = "MIT"
 readme = "README.md"
diff --git a/truss/tests/test_model_schema.py b/truss/tests/test_model_schema.py
index 70b6680e9..2214f5986 100644
--- a/truss/tests/test_model_schema.py
+++ b/truss/tests/test_model_schema.py
@@ -38,6 +38,14 @@ def test_truss_with_annotated_inputs_outputs():
             "generated_text": "value",
         }
 
+        # An invalid input
+
+        response = requests.post(full_url, json={"bad_key": "value"})
+
+        assert response.status_code == 400
+        assert "error" in response.json()
+        assert "validation error" in response.json()["error"]
+
         schema_response = requests.get(f"{truss_server_addr}/v1/models/model/schema")
 
         schema = schema_response.json()