From 2eb0c283e9a3f68ac5c1a874314710c495e46f72 Mon Sep 17 00:00:00 2001
From: Jiajun Xie <jiajunbernoulli@foxmail.com>
Date: Tue, 17 Mar 2026 13:25:08 +0800
Subject: [PATCH 1/2] fix(providers): handle empty choices in custom provider
 response

---
 nanobot/providers/custom_provider.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/nanobot/providers/custom_provider.py b/nanobot/providers/custom_provider.py
index e177e55..4bdeb54 100644
--- a/nanobot/providers/custom_provider.py
+++ b/nanobot/providers/custom_provider.py
@@ -54,6 +54,11 @@ class CustomProvider(LLMProvider):
             return LLMResponse(content=f"Error: {e}", finish_reason="error")
 
     def _parse(self, response: Any) -> LLMResponse:
+        if not response.choices:
+            return LLMResponse(
+                content="Error: API returned empty choices. This may indicate a temporary service issue or an invalid model response.",
+                finish_reason="error"
+            )
         choice = response.choices[0]
         msg = choice.message
         tool_calls = [

From 49fc50b1e623ee3a03a6e86b2dd6e90d956aaae2 Mon Sep 17 00:00:00 2001
From: Xubin Ren <xubinrencs@gmail.com>
Date: Tue, 17 Mar 2026 06:20:19 +0000
Subject: [PATCH 2/2] test(custom): cover empty choices response handling

---
 tests/test_custom_provider.py | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100644 tests/test_custom_provider.py

diff --git a/tests/test_custom_provider.py b/tests/test_custom_provider.py
new file mode 100644
index 0000000..463affe
--- /dev/null
+++ b/tests/test_custom_provider.py
@@ -0,0 +1,13 @@
+from types import SimpleNamespace
+
+from nanobot.providers.custom_provider import CustomProvider
+
+
+def test_custom_provider_parse_handles_empty_choices() -> None:
+    provider = CustomProvider()
+    response = SimpleNamespace(choices=[])
+
+    result = provider._parse(response)
+
+    assert result.finish_reason == "error"
+    assert "empty choices" in result.content