Simplify custom tool creation example (#102)

backend/app/core/graph/skills/__init__.py

@@ -6,7 +6,7 @@
     WikipediaAPIWrapper,
 )
 
-# from .calculator import calculator
+# from .calculator import multiply
 
 
 class SkillInfo(BaseModel):
@@ -26,13 +26,13 @@ class SkillInfo(BaseModel):
         description="Get information from Yahoo Finance News.",
         tool=YahooFinanceNewsTool(),
     ),
-    # "calculator": SkillInfo(
-    #     description=calculator.description,
-    #     tool=calculator,
+    # multiply.name: SkillInfo(
+    #     description=multiply.description,
+    #     tool=multiply,
     # ),
 }
 
 # To add more custom tools, follow these steps:
 # 1. Create a new Python file in the `skills` folder (e.g., `calculator.py`).
-# 2. Define your tool. Refer to `calculator.py` or see https://python.langchain.com/v0.1/docs/modules/tools/custom_tools/
+# 2. Define your tool. Refer to `calculator.py` or see https://python.langchain.com/v0.2/docs/how_to/custom_tools/
 # 3. Import your new tool here and add it to the `managed_skills` dictionary above.

backend/app/core/graph/skills/calculator.py

@@ -1,23 +1,13 @@
 # This is an example showing how to create a simple calculator skill
 
-from langchain.pydantic_v1 import BaseModel, Field
-from langchain.tools import StructuredTool
+from typing import Annotated
 
+from langchain_core.tools import tool
 
-class CalculatorInput(BaseModel):
-    a: int = Field(description="first number")
-    b: int = Field(description="second number")
 
-
-def multiply(a: int, b: int) -> int:
-    """Multiply two numbers."""
+@tool
+def multiply(
+    a: Annotated[int, "first number"], b: Annotated[int, "second number"]
+) -> int:
+    """Multiple two numbers."""
     return a * b
-
-
-calculator = StructuredTool.from_function(
-    func=multiply,
-    name="Calculator",
-    description="Useful for when you need to multiply two numbers.",
-    args_schema=CalculatorInput,
-    return_direct=True,
-)