diff --git a/tests/unit/test_reconcile.py b/tests/unit/test_reconcile.py
index c7443cce..1a93e726 100644
--- a/tests/unit/test_reconcile.py
+++ b/tests/unit/test_reconcile.py
@@ -23,6 +23,12 @@ def test_reconcile_post():
     assert res[0]["id"] == "Q18634850", res
 
 
+def test_reconcile_invalid():
+    queries = {"mutti": {"query": 37473874}}
+    resp = client.post("/reconcile/default", data={"queries": json.dumps(queries)})
+    assert resp.status_code == 400, resp.text
+
+
 def test_reconcile_suggest_entity_no_prefix():
     resp = client.get("/reconcile/default/suggest/entity")
     assert resp.status_code == 200, resp.text
@@ -37,8 +43,9 @@ def test_reconcile_suggest_entity_prefix():
     res = resp.json()["result"]
     assert len(res) > 0, res
     assert "Q7747" == res[0]["id"], res
-    name = ascii_text(res[0]["name"]).lower()
-    assert "vladimir" in name, name
+    name = ascii_text(res[0]["name"])
+    assert name is not None, res
+    assert "vladimir" in name.lower(), name
 
 
 def test_reconcile_suggest_entity_prefix_dummy():
diff --git a/yente/app.py b/yente/app.py
index 033408ba..e896fcfc 100644
--- a/yente/app.py
+++ b/yente/app.py
@@ -4,6 +4,7 @@
 from typing import AsyncGenerator, Dict, Type, Callable, Any, Coroutine, Union
 from contextlib import asynccontextmanager
 from elasticsearch import ApiError, TransportError
+from pydantic import ValidationError
 from fastapi import FastAPI
 from fastapi import Request, Response
 from fastapi.middleware.cors import CORSMiddleware
@@ -87,9 +88,16 @@ async def transport_error_handler(request: Request, exc: TransportError) -> Resp
     return JSONResponse(status_code=500, content={"detail": exc.message})
 
 
+async def validation_error_handler(request: Request, exc: ValidationError) -> Response:
+    log.warn(f"Validation error: {exc}")
+    body = {"detail": exc.title, "errors": exc.errors()}
+    return JSONResponse(status_code=400, content=body)
+
+
 HANDLERS: Dict[Union[Type[Exception], int], ExceptionHandler] = {
     ApiError: api_error_handler,
     TransportError: transport_error_handler,
+    ValidationError: validation_error_handler,
 }