Lorenze/max retry defaults tools (#3362)

* feat: enhance BaseTool and CrewStructuredTool with usage tracking

This commit introduces a mechanism to track the usage count of tools within the CrewAI framework. The `BaseTool` class now includes a `_increment_usage_count` method that updates the current usage count, which is also reflected in the associated `CrewStructuredTool`. Additionally, a new test has been added to ensure that the maximum usage count is respected when invoking tools, enhancing the overall reliability and functionality of the tool system.

* feat: add max usage count feature to tools documentation

This commit introduces a new section in the tools overview documentation that explains the maximum usage count feature for tools within the CrewAI framework. Users can now set a limit on how many times a tool can be used, enhancing control over tool usage. An example of implementing the `FileReadTool` with a maximum usage count is also provided, improving the clarity and usability of the documentation.

* undo field string

src/crewai/tools/base_tool.py

@@ -14,12 +14,14 @@ from pydantic import BaseModel as PydanticBaseModel
 
 from crewai.tools.structured_tool import CrewStructuredTool
 
+
 class EnvVar(BaseModel):
     name: str
     description: str
     required: bool = True
     default: Optional[str] = None
 
+
 class BaseTool(BaseModel, ABC):
     class _ArgsSchemaPlaceholder(PydanticBaseModel):
         pass
@@ -108,7 +110,7 @@ class BaseTool(BaseModel, ABC):
     def to_structured_tool(self) -> CrewStructuredTool:
         """Convert this tool to a CrewStructuredTool instance."""
         self._set_args_schema()
-        return CrewStructuredTool(
+        structured_tool = CrewStructuredTool(
             name=self.name,
             description=self.description,
             args_schema=self.args_schema,
@@ -117,6 +119,8 @@ class BaseTool(BaseModel, ABC):
             max_usage_count=self.max_usage_count,
             current_usage_count=self.current_usage_count,
         )
+        structured_tool._original_tool = self
+        return structured_tool
 
     @classmethod
     def from_langchain(cls, tool: Any) -> "BaseTool":
@@ -276,7 +280,9 @@ def to_langchain(
     return [t.to_structured_tool() if isinstance(t, BaseTool) else t for t in tools]
 
 
-def tool(*args, result_as_answer: bool = False, max_usage_count: int | None = None) -> Callable:
+def tool(
+    *args, result_as_answer: bool = False, max_usage_count: int | None = None
+) -> Callable:
     """
     Decorator to create a tool from a function.