Add Llama 3.x validation at bind_tools time

- Llama 3.x validation happens early at bind_tools time
- Cohere validation happens at provider level (_prepare_request time)
- All 16 parallel tool calling tests now pass

Author: fede-kamel

libs/oci/langchain_oci/chat_models/oci_generative_ai.py

@@ -861,14 +861,6 @@ def _should_allow_more_tool_calls(
 
         # Add parallel tool calls support (GenericChatRequest models)
         if "is_parallel_tool_calls" in kwargs:
-            # Validate Llama 3.x doesn't support parallel tool calls
-            model_id = self.llm.model_id
-            if "llama" in model_id.lower() and not self.llm._supports_parallel_tool_calls(model_id):
-                raise ValueError(
-                    f"Parallel tool calls not supported for {model_id}. "
-                    "Only Llama 4+ models support this feature. "
-                    "Llama 3.x (including 3.3) don't support parallel calls."
-                )
             result["is_parallel_tool_calls"] = kwargs["is_parallel_tool_calls"]
 
         return result
@@ -1321,7 +1313,13 @@ def bind_tools(
             else self.parallel_tool_calls
         )
         if use_parallel:
-            # Store the parameter; validation happens in provider
+            # Validate Llama 3.x doesn't support parallel tool calls (early check)
+            if "llama" in self.model_id.lower() and not self._supports_parallel_tool_calls(self.model_id):
+                raise ValueError(
+                    f"Parallel tool calls not supported for {self.model_id}. "
+                    "Only Llama 4+ models support this feature. "
+                    "Llama 3.x (including 3.3) don't support parallel calls."
+                )
             kwargs["is_parallel_tool_calls"] = True
 
         return super().bind(tools=formatted_tools, **kwargs)