fix: refresh copilot token before requests

Address PR review feedback by avoiding an async method reference as the OpenAI client api_key.

Initialize the client with a placeholder key, refresh the Copilot token before each chat/chat_stream call, and update the runtime client api_key before dispatch.

Add a regression test that verifies the client api_key is refreshed to a real string before chat requests.

Generated with GitHub Copilot, GPT-5.4.

nanobot/providers/github_copilot_provider.py

@@ -164,7 +164,7 @@ class GitHubCopilotProvider(OpenAICompatProvider):
         self._copilot_access_token: str | None = None
         self._copilot_expires_at: float = 0.0
         super().__init__(
-            api_key=self._get_copilot_access_token,
+            api_key="no-key",
             api_base=DEFAULT_COPILOT_BASE_URL,
             default_model=default_model,
             extra_headers={
@@ -205,3 +205,53 @@ class GitHubCopilotProvider(OpenAICompatProvider):
             self._copilot_expires_at = time.time() + int(refresh_in)
         self._copilot_access_token = str(token)
         return self._copilot_access_token
+
+    async def _refresh_client_api_key(self) -> str:
+        token = await self._get_copilot_access_token()
+        self.api_key = token
+        self._client.api_key = token
+        return token
+
+    async def chat(
+        self,
+        messages: list[dict[str, object]],
+        tools: list[dict[str, object]] | None = None,
+        model: str | None = None,
+        max_tokens: int = 4096,
+        temperature: float = 0.7,
+        reasoning_effort: str | None = None,
+        tool_choice: str | dict[str, object] | None = None,
+    ):
+        await self._refresh_client_api_key()
+        return await super().chat(
+            messages=messages,
+            tools=tools,
+            model=model,
+            max_tokens=max_tokens,
+            temperature=temperature,
+            reasoning_effort=reasoning_effort,
+            tool_choice=tool_choice,
+        )
+
+    async def chat_stream(
+        self,
+        messages: list[dict[str, object]],
+        tools: list[dict[str, object]] | None = None,
+        model: str | None = None,
+        max_tokens: int = 4096,
+        temperature: float = 0.7,
+        reasoning_effort: str | None = None,
+        tool_choice: str | dict[str, object] | None = None,
+        on_content_delta: Callable[[str], None] | None = None,
+    ):
+        await self._refresh_client_api_key()
+        return await super().chat_stream(
+            messages=messages,
+            tools=tools,
+            model=model,
+            max_tokens=max_tokens,
+            temperature=temperature,
+            reasoning_effort=reasoning_effort,
+            tool_choice=tool_choice,
+            on_content_delta=on_content_delta,
+        )

tests/cli/test_commands.py

@@ -357,6 +357,35 @@ def test_github_copilot_provider_strips_prefixed_model_name():
     assert kwargs["model"] == "gpt-5.1"
 
 
+@pytest.mark.asyncio
+async def test_github_copilot_provider_refreshes_client_api_key_before_chat():
+    from nanobot.providers.github_copilot_provider import GitHubCopilotProvider
+
+    mock_client = MagicMock()
+    mock_client.api_key = "no-key"
+    mock_client.chat.completions.create = AsyncMock(return_value={
+        "choices": [{"message": {"content": "ok"}, "finish_reason": "stop"}],
+        "usage": {"prompt_tokens": 1, "completion_tokens": 1, "total_tokens": 2},
+    })
+
+    with patch("nanobot.providers.openai_compat_provider.AsyncOpenAI", return_value=mock_client):
+        provider = GitHubCopilotProvider(default_model="github-copilot/gpt-5.1")
+
+    provider._get_copilot_access_token = AsyncMock(return_value="copilot-access-token")
+
+    response = await provider.chat(
+        messages=[{"role": "user", "content": "hi"}],
+        model="github-copilot/gpt-5.1",
+        max_tokens=16,
+        temperature=0.1,
+    )
+
+    assert response.content == "ok"
+    assert provider._client.api_key == "copilot-access-token"
+    provider._get_copilot_access_token.assert_awaited_once()
+    mock_client.chat.completions.create.assert_awaited_once()
+
+
 def test_openai_codex_strip_prefix_supports_hyphen_and_underscore():
     assert _strip_model_prefix("openai-codex/gpt-5.1-codex") == "gpt-5.1-codex"
     assert _strip_model_prefix("openai_codex/gpt-5.1-codex") == "gpt-5.1-codex"