fixed a bug

sentence_api/tests/test_ai_tutor.py

@@ -47,6 +47,21 @@ def test_ai_tutor_parses_chat_completion(monkeypatch):
     assert timeout == 1.5
 
 
+def test_ai_tutor_resolves_openai_compatible_base_url(monkeypatch):
+    endpoints = []
+
+    def fake_post(endpoint, **kwargs):
+        endpoints.append(endpoint)
+        return FakeResponse(body={"choices": [{"message": {"content": "ok"}}]})
+
+    monkeypatch.setattr("sentence_api.ai_tutor.requests.post", fake_post)
+    tutor = AITutor("https://ai.test:8080/v1", "secret", "test-model", 1)
+
+    assert tutor.explain("Hello.") == "ok"
+    assert endpoints == ["https://ai.test:8080/v1/chat/completions"]
+    assert tutor.request_url == "https://ai.test:8080/v1/chat/completions"
+
+
 def test_ai_tutor_rejects_unexpected_response(monkeypatch):
     monkeypatch.setattr(
         "sentence_api.ai_tutor.requests.post",