add search_tool.py

src/main.py

@@ -1,53 +0,0 @@
-"""
-Deep Agents from Scratch example.
-This script demonstrates a simple agent that searches the web and writes results to files.
-It uses the `deep-agents-from-scratch` package as required by the assignment.
-"""
-
-from __future__ import annotations
-
-import os
-from pathlib import Path
-
-# Ensure dependencies are available
-try:
-    from deep_agents_from_scratch.research_tools import tavily_search, think_tool
-except Exception as e:  # pragma: no cover - defensive
-    raise RuntimeError("deep-agents-from-scratch not installed") from e
-
-from langchain.agents import create_agent
-from langchain.chat_models import init_chat_model
-from deep_agents_from_scratch.state import DeepAgentState
-from deep_agents_from_scratch.file_tools import ls, read_file, write_file
-
-# Simple prompt for the agent
-SYSTEM_PROMPT = """
-You are a research assistant. Use web search to gather information and store results in files.
-After each search, reflect on what you found.
-"""
-
-model = init_chat_model(model="anthropic:claude-sonnet-4-20250514", temperature=0)
-
-# Tools available to the agent
-TOOLS = [tavily_search, think_tool, ls, read_file, write_file]
-
-agent = create_agent(
-    model,
-    TOOLS,
-    system_prompt=SYSTEM_PROMPT,
-    state_schema=DeepAgentState,
-)
-
-def run_query(query: str) -> None:
-    """Run a single query and print the resulting messages."""
-    result = agent.invoke({"messages": [{"role": "user", "content": query}]})
-    for msg in result["messages"]:
-        print(msg.content)
-
-if __name__ == "__main__":  # pragma: no cover - entry point
-    import argparse
-
-    parser = argparse.ArgumentParser(description="Run deep agent example")
-    parser.add_argument("query", help="Query to search for")
-    args = parser.parse_args()
-    run_query(args.query)

src/search_tool.py

@@ -0,0 +1,53 @@
+"""Internet search tool using DuckDuckGo."""
+
+import json
+import requests
+from bs4 import BeautifulSoup
+from langchain.tools import tool
+
+
+@tool
+def internet_search(query: str) -> str:
+    """
+    Search DuckDuckGo for information.
+    
+    Args:
+        query: Search query string
+        
+    Returns:
+        JSON string with search results (url, title, snippet)
+    """
+    headers = {
+        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36'
+    }
+    url = "https://html.duckduckgo.com/html/"
+    params = {"q": query}
+    
+    try:
+        response = requests.get(url, params=params, headers=headers, timeout=10)
+        response.raise_for_status()
+        
+        soup = BeautifulSoup(response.text, "html.parser")
+        results = []
+        
+        # Parse search results
+        for result in soup.select(".result")[:3]:
+            title_elem = result.select_one(".result__a")
+            link_elem = result.select_one(".result__url")
+            snippet_elem = result.select_one(".result__snippet")
+            
+            if title_elem:
+                title = title_elem.get_text(strip=True)
+                link = link_elem.get("href", "") if link_elem else ""
+                snippet = snippet_elem.get_text(strip=True) if snippet_elem else ""
+                
+                results.append({
+                    "title": title,
+                    "url": link,
+                    "snippet": snippet
+                })
+        
+        return json.dumps(results, ensure_ascii=False, indent=2)
+        
+    except requests.RequestException as e:
+        return json.dumps({"error": f"Search failed: {str(e)}"})