custom_tools.py

import requests
from duckduckgo_search import DDGS
from langchain_core.tools import tool

@tool
def reverse_text(input: str) -> str:
    """Reverse the characters in a text or string.

    Args:
        query: The text or string to reverse.
    """
    return input[::-1]

@tool
def web_search(query: str) -> str:
    """Perform a web search using DuckDuckGo and return the top 3 summarized results.

    Args:
        query: The search query to look up.
    """
    try:
        results = []
        with DDGS() as ddgs:
            for r in ddgs.text(query, max_results=3):
                title = r.get("title", "")
                snippet = r.get("body", "")
                url = r.get("href", "")
                if title and snippet:
                    results.append(f"{title}: {snippet} (URL: {url})")
        if not results:
            return "No results found."
        return "\n\n---\n\n".join(results)
    except Exception as e:
        return f"Web search error: {e}"

@tool
def calculate(expression: str) -> str:
    """Evaluate a simple math expression and return the result.

    Args:
        expression: A string containing the math expression to evaluate.
    """
    try:
        allowed_names = {
            "abs": abs,
            "round": round,
            "min": min,
            "max": max,
            "pow": pow,
        }
        result = eval(expression, {"__builtins__": None}, allowed_names)
        return str(result)
    except Exception as e:
        return f"Calculation error: {e}"

@tool
def wikipedia_summary(query: str) -> str:
    """Retrieve a summary of a topic from Wikipedia.

    Args:
        query: The subject or topic to summarize.
    """
    try:
        response = requests.get(
            f"https://en.wikipedia.org/api/rest_v1/page/summary/{query}", timeout=10
        )
        response.raise_for_status()
        data = response.json()
        return data.get("extract", "No summary found.")
    except Exception as e:
        return f"Wikipedia error: {e}"

@tool
def define_term(term: str) -> str:
    """Provide a dictionary-style definition of a given term using an online API.

    Args:
        term: The word or term to define.
    """
    try:
        response = requests.get(
            f"https://api.dictionaryapi.dev/api/v2/entries/en/{term}", timeout=10
        )
        response.raise_for_status()
        data = response.json()
        meanings = data[0].get("meanings", [])
        if meanings:
            defs = meanings[0].get("definitions", [])
            if defs:
                return defs[0].get("definition", "Definition not found.")
        return "Definition not found."
    except Exception as e:
        return f"Definition error: {e}"

# List of tools to register with your agent
TOOLS = [web_search, calculate, wikipedia_summary, define_term, reverse_text]