@Tool decorator not working

[YogeshSaini85]

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Example Code

@Tool
def reset_process_tool():
    """Can be used to reset process when user wants to start over"""
    process.reset()

Description

I have used @tool decorator on a function but when I run it in pycharm I get this error:

@Tool
 ^^^^

TypeError: Tool.init() missing 2 required positional arguments: 'func' and 'description'

System Info

langchain==0.2.16
langchain-community==0.2.16
langchain-core==0.2.38
langchain-openai==0.1.7
langchain-text-splitters==0.2.4

[dosubot[bot]]

The @Tool decorator is causing a TypeError because it is being used incorrectly. The correct usage of the Tool class requires either positional or keyword arguments for name, func, and description.

In your provided code, the @Tool decorator is used without providing the required arguments. Here is how you can correct it:

@Tool(name="reset_process_tool", func=reset_process_tool, description="Can be used to reset process when user wants to start over")
def reset_process_tool():
    """Can be used to reset process when user wants to start over"""
    process.reset()

Alternatively, you can use the from_function class method to create the tool:

reset_process_tool = Tool.from_function(
    func=reset_process_tool,
    name="reset_process_tool",
    description="Can be used to reset process when user wants to start over"
)

Ensure the decorator is properly defined to handle the function and description arguments. The Tool class in LangChain requires these parameters to be provided during initialization ^[1][2].

To continue talking to Dosu, mention @dosu.

[YogeshSaini85]

Okay fine, but this documentation says I could just use @tool and it will take the function name by default.
https://python.langchain.com/v0.2/docs/how_to/custom_tools/

---Excerpt from the documentation-------

This @tool decorator is the simplest way to define a custom tool. The decorator uses the function name as the tool name by default, but this can be overridden by passing a string as the first argument. Additionally, the decorator will use the function's docstring as the tool's description - so a docstring MUST be provided.

from langchain_core.tools import tool

@tool
def multiply(a: int, b: int) -> int:
"""Multiply two numbers."""
return a * b

print(multiply.name)
print(multiply.description)
print(multiply.args)

[YogeshSaini85]

@dosu Even this does not work, it gives this error:

Unresolved reference 'reset_process_tool'

[YogeshSaini85]

@dosu Even this does not work, it gives this error:

Unresolved reference 'reset_process_tool'

[dosubot[bot]]

The "Unresolved reference 'reset_process_tool'" error likely occurs because the reset_process_tool function is not defined or imported in the scope where the @tool decorator is being applied. Ensure that the reset_process_tool function is defined before applying the @tool decorator, like so:

from langchain_core.tools import tool

@tool
def reset_process_tool():
    """Can be used to reset process when user wants to start over"""
    process.reset()

If the function is defined in another module, make sure to import it correctly:

from some_module import reset_process_tool
from langchain_core.tools import tool

@tool
def reset_process_tool():
    """Can be used to reset process when user wants to start over"""
    process.reset()

Additionally, ensure you have the correct import statement for the tool decorator:

from langchain_core.tools import tool

This should resolve the "Unresolved reference 'reset_process_tool'" error ^[1].

To continue talking to Dosu, mention @dosu.

[YogeshSaini85]

@dosu you only suggest me below code which is producing error:

@tool(name="reset_process_tool", func=reset_process_tool, description="Can be used to reset process when user wants to start over")
def reset_process_tool():
"""Can be used to reset process when user wants to start over"""
process.reset()

[dosubot[bot]]

The error occurs because the correct decorator to use is @tool instead of @Tool. Here is the corrected code:

from langchain_core.tools import tool

@tool(name="reset_process_tool", description="Can be used to reset process when user wants to start over")
def reset_process_tool():
    """Can be used to reset process when user wants to start over"""
    process.reset()

Make sure you have the correct import statement:

from langchain_core.tools import tool

This should resolve the issue ^[1].

To continue talking to Dosu, mention @dosu.

[eyurtsev]

The tool decorator is a lower case tool as opposed to the Tool class

from langchain_core.tools import tool

@tool
def foo():

[YogeshSaini85]

Omg I'm such an idiot.. Thank you so much for the help.