fix: refactor code structure for improved readability and maintainability

nanobot/cli/commands.py

@@ -16,6 +16,7 @@ from rich.table import Table
 from rich.text import Text
 
 from nanobot import __version__, __logo__
+from nanobot.config.schema import Config
 
 app = typer.Typer(
     name="nanobot",
@@ -295,21 +296,33 @@ This file stores important information that should persist across sessions.
         console.print("  [dim]Created memory/MEMORY.md[/dim]")
 
 
-def _make_provider(config):
+def _make_provider(config: Config):
     """Create LiteLLMProvider from config. Exits if no API key found."""
     from nanobot.providers.litellm_provider import LiteLLMProvider
-    p = config.get_provider()
+    from nanobot.providers.openai_codex_provider import OpenAICodexProvider
+
     model = config.agents.defaults.model
-    if not (p and p.api_key) and not model.startswith("bedrock/"):
+    provider_name = config.get_provider_name(model)
+    p = config.get_provider(model)
+
+    # OpenAI Codex (OAuth): don't route via LiteLLM; use the dedicated implementation.
+    if provider_name == "openai_codex" or model.startswith("openai-codex/"):
+        return OpenAICodexProvider(
+            default_model=model,
+            api_base=p.api_base if p else None,
+        )
+
+    if not model.startswith("bedrock/") and not (p and p.api_key):
         console.print("[red]Error: No API key configured.[/red]")
         console.print("Set one in ~/.nanobot/config.json under providers section")
         raise typer.Exit(1)
+
     return LiteLLMProvider(
         api_key=p.api_key if p else None,
-        api_base=config.get_api_base(),
+        api_base=config.get_api_base(model),
         default_model=model,
         extra_headers=p.extra_headers if p else None,
-        provider_name=config.get_provider_name(),
+        provider_name=provider_name,
     )
 
 

nanobot/providers/litellm_provider.py

@@ -54,6 +54,9 @@ class LiteLLMProvider(LLMProvider):
         spec = self._gateway or find_by_model(model)
         if not spec:
             return
+        if not spec.env_key:
+            # OAuth/provider-only specs (for example: openai_codex)
+            return
 
         # Gateway/local overrides existing env; standard provider doesn't
         if self._gateway:

nanobot/providers/openai_codex_provider.py

@@ -77,7 +77,6 @@ class OpenAICodexProvider(LLMProvider):
     def get_default_model(self) -> str:
         return self.default_model
 
-
 def _strip_model_prefix(model: str) -> str:
     if model.startswith("openai-codex/"):
         return model.split("/", 1)[1]
@@ -95,7 +94,6 @@ def _build_headers(account_id: str, token: str) -> dict[str, str]:
         "content-type": "application/json",
     }
 
-
 async def _request_codex(
     url: str,
     headers: dict[str, str],
@@ -109,7 +107,6 @@ async def _request_codex(
                 raise RuntimeError(_friendly_error(response.status_code, text.decode("utf-8", "ignore")))
             return await _consume_sse(response)
 
-
 def _convert_tools(tools: list[dict[str, Any]]) -> list[dict[str, Any]]:
     # Nanobot tool definitions already use the OpenAI function schema.
     converted: list[dict[str, Any]] = []
@@ -140,7 +137,6 @@ def _convert_tools(tools: list[dict[str, Any]]) -> list[dict[str, Any]]:
         )
     return converted
 
-
 def _convert_messages(messages: list[dict[str, Any]]) -> tuple[str, list[dict[str, Any]]]:
     system_prompt = ""
     input_items: list[dict[str, Any]] = []
@@ -200,7 +196,6 @@ def _convert_messages(messages: list[dict[str, Any]]) -> tuple[str, list[dict[st
 
     return system_prompt, input_items
 
-
 def _convert_user_message(content: Any) -> dict[str, Any]:
     if isinstance(content, str):
         return {"role": "user", "content": [{"type": "input_text", "text": content}]}
@@ -234,12 +229,10 @@ def _split_tool_call_id(tool_call_id: Any) -> tuple[str, str | None]:
         return tool_call_id, None
     return "call_0", None
 
-
 def _prompt_cache_key(messages: list[dict[str, Any]]) -> str:
     raw = json.dumps(messages, ensure_ascii=True, sort_keys=True)
     return hashlib.sha256(raw.encode("utf-8")).hexdigest()
 
-
 async def _iter_sse(response: httpx.Response) -> AsyncGenerator[dict[str, Any], None]:
     buffer: list[str] = []
     async for line in response.aiter_lines():
@@ -259,9 +252,6 @@ async def _iter_sse(response: httpx.Response) -> AsyncGenerator[dict[str, Any],
             continue
         buffer.append(line)
 
-
-
-
 async def _consume_sse(response: httpx.Response) -> tuple[str, list[ToolCallRequest], str]:
     content = ""
     tool_calls: list[ToolCallRequest] = []
@@ -318,7 +308,6 @@ async def _consume_sse(response: httpx.Response) -> tuple[str, list[ToolCallRequ
 
     return content, tool_calls, finish_reason
 
-
 def _map_finish_reason(status: str | None) -> str:
     if not status:
         return "stop"
@@ -330,7 +319,6 @@ def _map_finish_reason(status: str | None) -> str:
         return "error"
     return "stop"
 
-
 def _friendly_error(status_code: int, raw: str) -> str:
     if status_code == 429:
         return "ChatGPT usage quota exceeded or rate limit triggered. Please try again later."