diff --git a/swh/search/api/server.py b/swh/search/api/server.py
index 112c903..25d491a 100644
--- a/swh/search/api/server.py
+++ b/swh/search/api/server.py
@@ -1,100 +1,106 @@
 # Copyright (C) 2019-2021  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import logging
 import os
 from typing import Any, Dict
 
 from swh.core import config
 from swh.core.api import RPCServerApp
 from swh.core.api import encode_data_server as encode_data
 from swh.core.api import error_handler
 from swh.search.metrics import timed
 
 from .. import get_search
+from ..exc import SearchException
 from ..interface import SearchInterface
 
 logger = logging.getLogger(__name__)
 
 
 def _get_search():
     global search
     if not search:
         search = get_search(**app.config["search"])
 
     return search
 
 
 app = RPCServerApp(__name__, backend_class=SearchInterface, backend_factory=_get_search)
 
 search = None
 
 
+@app.errorhandler(SearchException)
+def search_error_handler(exception):
+    return error_handler(exception, encode_data, status_code=400)
+
+
 @app.errorhandler(Exception)
 def my_error_handler(exception):
     return error_handler(exception, encode_data)
 
 
 @app.route("/")
 @timed
 def index():
     return "SWH Search API server"
 
 
 @app.before_first_request
 def initialized_index():
     search = _get_search()
     logger.info("Initializing indexes with configuration: ", search.origin_config)
     search.initialize()
 
 
 api_cfg = None
 
 
 def load_and_check_config(config_file: str) -> Dict[str, Any]:
     """Check the minimal configuration is set to run the api or raise an
        error explanation.
 
     Args:
         config_file: Path to the configuration file to load
         type: configuration type. For 'local' type, more
                     checks are done.
 
     Raises:
         Error if the setup is not as expected
 
     Returns:
         configuration as a dict
 
     """
     if not config_file:
         raise EnvironmentError("Configuration file must be defined")
 
     if not os.path.exists(config_file):
         raise FileNotFoundError("Configuration file %s does not exist" % (config_file,))
 
     cfg = config.read(config_file)
     if "search" not in cfg:
         raise KeyError("Missing 'search' configuration")
 
     return cfg
 
 
 def make_app_from_configfile():
     """Run the WSGI app from the webserver, loading the configuration from
        a configuration file.
 
        SWH_CONFIG_FILENAME environment variable defines the
        configuration path to load.
 
     """
     global api_cfg
     if not api_cfg:
         config_file = os.environ.get("SWH_CONFIG_FILENAME")
         api_cfg = load_and_check_config(config_file)
         app.config.update(api_cfg)
     handler = logging.StreamHandler()
     app.logger.addHandler(handler)
     return app