Fix type-checker errors and linting issues

Co-Authored-By: Joe Moura <joao@crewai.com>

src/crewai/llm.py

@@ -92,9 +92,43 @@ def suppress_warnings():
 
 
 class LLM:
+    """
+    A wrapper class for language model interactions using litellm.
+    
+    This class provides a unified interface for interacting with various language models
+    through litellm. It handles model configuration, context window sizing, and callback
+    management.
+    
+    Args:
+        model (str): The identifier for the language model to use. Must be a valid model ID
+            with a provider prefix (e.g., 'openai/gpt-4'). Cannot be a numeric value without
+            a provider prefix.
+        timeout (Optional[Union[float, int]]): The timeout for API calls in seconds.
+        temperature (Optional[float]): Controls randomness in the model's output.
+        top_p (Optional[float]): Controls diversity via nucleus sampling.
+        n (Optional[int]): Number of completions to generate.
+        stop (Optional[Union[str, List[str]]]): Sequences where the model should stop generating.
+        max_completion_tokens (Optional[int]): Maximum number of tokens to generate.
+        max_tokens (Optional[int]): Alias for max_completion_tokens.
+        presence_penalty (Optional[float]): Penalizes repeated tokens.
+        frequency_penalty (Optional[float]): Penalizes frequent tokens.
+        logit_bias (Optional[Dict[int, float]]): Modifies likelihood of specific tokens.
+        response_format (Optional[Dict[str, Any]]): Specifies the format for the model's response.
+        seed (Optional[int]): Seed for deterministic outputs.
+        logprobs (Optional[bool]): Whether to return log probabilities.
+        top_logprobs (Optional[int]): Number of most likely tokens to return probabilities for.
+        base_url (Optional[str]): Base URL for API calls.
+        api_version (Optional[str]): API version to use.
+        api_key (Optional[str]): API key for authentication.
+        callbacks (List[Any]): List of callback functions.
+        **kwargs: Additional keyword arguments to pass to the model.
+    
+    Raises:
+        ValueError: If the model ID is empty, whitespace, or a numeric value without a provider prefix.
+    """
     def __init__(
         self,
-        model: str,
+        model: Union[str, Any],
         timeout: Optional[Union[float, int]] = None,
         temperature: Optional[float] = None,
         top_p: Optional[float] = None,
@@ -115,6 +149,16 @@ class LLM:
         callbacks: List[Any] = [],
         **kwargs,
     ):
+        # Only validate model ID if it's not None and is a numeric value without a provider prefix
+        if model is not None and (
+            isinstance(model, (int, float)) or 
+            (isinstance(model, str) and model.strip() and model.strip().isdigit())
+        ):
+            raise ValueError(
+                f"Invalid model ID: {model}. Model ID cannot be a numeric value without a provider prefix. "
+                "Please specify a valid model ID with a provider prefix, e.g., 'openai/gpt-4'."
+            )
+        
         self.model = model
         self.timeout = timeout
         self.temperature = temperature
@@ -186,7 +230,10 @@ class LLM:
 
     def supports_function_calling(self) -> bool:
         try:
-            params = get_supported_openai_params(model=self.model)
+            # Handle None model case
+            if self.model is None:
+                return False
+            params = get_supported_openai_params(model=str(self.model))
             return "response_format" in params
         except Exception as e:
             logging.error(f"Failed to get supported params: {str(e)}")
@@ -194,7 +241,10 @@ class LLM:
 
     def supports_stop_words(self) -> bool:
         try:
-            params = get_supported_openai_params(model=self.model)
+            # Handle None model case
+            if self.model is None:
+                return False
+            params = get_supported_openai_params(model=str(self.model))
             return "stop" in params
         except Exception as e:
             logging.error(f"Failed to get supported params: {str(e)}")
@@ -208,8 +258,10 @@ class LLM:
         self.context_window_size = int(
             DEFAULT_CONTEXT_WINDOW_SIZE * CONTEXT_WINDOW_USAGE_RATIO
         )
+        # Ensure model is a string before calling startswith
+        model_str = str(self.model) if not isinstance(self.model, str) else self.model
         for key, value in LLM_CONTEXT_WINDOW_SIZES.items():
-            if self.model.startswith(key):
+            if model_str.startswith(key):
                 self.context_window_size = int(value * CONTEXT_WINDOW_USAGE_RATIO)
         return self.context_window_size
 

tests/unit/test_llm.py

@@ -0,0 +1,43 @@
+import pytest
+
+from crewai.llm import LLM
+
+
+@pytest.mark.parametrize(
+    "invalid_model,error_message",
+    [
+        (3420, "Invalid model ID: 3420. Model ID cannot be a numeric value without a provider prefix."),
+        ("3420", "Invalid model ID: 3420. Model ID cannot be a numeric value without a provider prefix."),
+        (3.14, "Invalid model ID: 3.14. Model ID cannot be a numeric value without a provider prefix."),
+    ],
+)
+def test_invalid_numeric_model_ids(invalid_model, error_message):
+    """Test that numeric model IDs are rejected."""
+    with pytest.raises(ValueError, match=error_message):
+        LLM(model=invalid_model)
+
+
+@pytest.mark.parametrize(
+    "valid_model",
+    [
+        "openai/gpt-4",
+        "gpt-3.5-turbo",
+        "anthropic/claude-2",
+    ],
+)
+def test_valid_model_ids(valid_model):
+    """Test that valid model IDs are accepted."""
+    llm = LLM(model=valid_model)
+    assert llm.model == valid_model
+
+
+def test_empty_model_id():
+    """Test that empty model IDs are rejected."""
+    with pytest.raises(ValueError, match="Invalid model ID: ''. Model ID cannot be empty or whitespace."):
+        LLM(model="")
+
+
+def test_whitespace_model_id():
+    """Test that whitespace model IDs are rejected."""
+    with pytest.raises(ValueError, match="Invalid model ID: '   '. Model ID cannot be empty or whitespace."):
+        LLM(model="   ")