diff --git a/backend/openai_client.py b/backend/openai_client.py
index f36d192..8a5910e 100644
--- a/backend/openai_client.py
+++ b/backend/openai_client.py
@@ -1,14 +1,28 @@
 from openai import OpenAI
-import os
 
-client = OpenAI(
-    api_key=os.getenv('OPENAI_API_KEY')
-)
+from backend.config_store import get_openai_key, get_openai_model
+
+
+class OpenAIConfigurationError(Exception):
+    pass
+
+
+def _client() -> OpenAI:
+    api_key = get_openai_key()
+
+    if not api_key:
+        raise OpenAIConfigurationError(
+            'OpenAI API key is not configured'
+        )
+
+    return OpenAI(api_key=api_key)
 
 
 async def ask_ai(prompt: str):
+    client = _client()
+
     response = client.responses.create(
-        model='gpt-5',
+        model=get_openai_model(),
         input=prompt
     )