refactor: Move BaseTool to main package and centralize tool description generation

[c0dezli]

Description:

Problem

Currently, we have:

1. The BaseTool definition in crewai-tools package, which should focus on tool implementations rather than core definitions
2. Duplicated tool description generation logic across three locations:
   • agent.py: _render_text_description_and_args()
   • tool_usage.py: _render()
   • base_tool.py: _generate_description()

Proposed Changes

1. Move BaseTool class from crewai-tools to the main crewai package

   • This establishes crewai as the source of core tool abstractions
   • Allows crewai-tools to focus purely on tool implementations

2. Create a centralized tool description generator in the moved base_tool.py:

    def _generate_description(self):
        args_schema = {
            name: {
                "description": field.description,
                "type": BaseTool._get_arg_annotations(field.annotation),
            }
            for name, field in self.args_schema.model_fields.items()
        }

        description = self.description.replace("\n", " ")
        self.description = f"Tool Name: {self.name}\nTool Arguments: {args_schema}\nTool Description: {description}"

    @staticmethod
    def _get_arg_annotations(annotation: type[Any] | None) -> str:
        origin = get_origin(annotation)
        args = get_args(annotation)

        if origin is None:
            return (
                annotation.__name__
                if hasattr(annotation, "__name__")
                else str(annotation)
            )

        if args:
            args_str = ", ".join(BaseTool._get_arg_annotations(arg) for arg in args)
            return f"{origin.__name__}[{args_str}]"

        return origin.__name__

3. Update all existing implementations to use this centralized function
   • Replace _render_text_description_and_args() in agent.py
   • Replace _render() in tool_usage.py
   • Remove duplicated code from crewai-tools

Benefits

• Proper separation of concerns between packages
  • crewai: core abstractions and interfaces
  • crewai-tools: implementations and utilities
• Single source of truth for tool descriptions
• Improved maintainability
• Consistent tool description format across the system

Breaking Changes

• Projects directly importing BaseTool from crewai-tools will need to update their imports
• Will require a major version bump for crewai-tools

Migration Guide

For users importing from crewai-tools:

# Old
from crewai_tools import BaseTool

# New
from crewai.tools import BaseTool

Related Issues: #1511

[bhancockio]

I was getting some errors with func not existing on cls.

Let's change this to something like this unless you have another suggestion:

 @classmethod
  def from_langchain(cls, tool: StructuredTool) -> "BaseTool":
      if cls == Tool:
          if tool.func is None:
              raise ValueError("StructuredTool must have a callable 'func'")
          return Tool(
              name=tool.name,
              description=tool.description,
              args_schema=tool.args_schema,
              func=tool.func,
          )
      raise NotImplementedError(f"from_langchain not implemented for {cls.__name__}")
      ```

[bhancockio]

This is an amazing PR @c0dezli !!!

Thank you so much. There was only one linting on the from_langchain function

[c0dezli]

sweet! just made the change. thanks for reviewing!

[c0dezli]

PR for crewAI-tools linked here: crewAIInc/crewAI-tools#119