""" Tavily-based Tools for Deep Research Agent Provides web search with content using the Tavily API. The search returns full page content, eliminating the need for separate scraping. The research() tool wraps an internal Deep Agent that runs in a separate thread to prevent subagent text from leaking to the frontend via LangChain callback propagation. """ import os from typing import Any from concurrent.futures import ThreadPoolExecutor from langchain_core.tools import tool from langchain_core.messages import HumanMessage from tavily import TavilyClient def _do_internet_search(query: str, max_results: int = 5) -> list[dict[str, Any]]: """Core search logic - callable as regular function. Args: query: The search query string max_results: Maximum number of results to return (default: 5) Returns: List of dicts with url, title, and content for each result """ print(f"[TOOL] internet_search: query='{query}', max_results={max_results}") tavily_key = os.environ.get("TAVILY_API_KEY") if not tavily_key: raise RuntimeError("TAVILY_API_KEY not set") try: client = TavilyClient(api_key=tavily_key) results = client.search( query=query, max_results=max_results, include_raw_content=False, # Disable raw content for performance topic="general", ) # Format results for agent consumption formatted_results = [] for r in results.get("results", []): formatted_results.append( { "url": r.get("url", ""), "title": r.get("title", ""), "content": (r.get("content") or "")[ :3000 ], # Truncate to 3000 chars } ) print(f"[TOOL] internet_search: found {len(formatted_results)} results") return formatted_results except Exception as e: print(f"[TOOL] internet_search error: {e}") return [{"error": str(e)}] @tool def internet_search(query: str, max_results: int = 5) -> list[dict[str, Any]]: """Search the web and return results with content. Use this tool to find relevant web pages about a topic. Returns search results including the page content for analysis. Args: query: The search query string max_results: Maximum number of results to return (default: 5) Returns: List of dicts with url, title, and content for each result """ return _do_internet_search(query, max_results) @tool def research(query: str) -> dict: """ Research a topic using web search. Returns structured data with sources. This tool creates an internal Deep Agent that runs in a SEPARATE THREAD to prevent LangChain callback propagation. The thread has isolated execution context, so the internal agent's events don't leak to the parent's astream_events() stream. Args: query: The research query/topic to investigate Returns: dict: { "summary": str - Prose summary of findings, "sources": list[dict] - [{url, title, content, status}, ...] } """ print(f"[TOOL] research: query='{query}' (using thread isolation)") from deepagents import create_deep_agent from langchain_openai import ChatOpenAI def _run_research_isolated(): """ Runs in separate thread with no inherited LangChain context. This breaks callback propagation at the OS level. """ # Capture internet_search results search_results = [] # Wrapper to capture results while passing through to agent def internet_search_tracked(query: str, max_results: int = 5): """Search the web and return results with content. Args: query: The search query string max_results: Maximum number of results to return (default: 5) Returns: List of dicts with url, title, and content for each result """ results = _do_internet_search(query, max_results) search_results.extend(results) return results model_name = os.environ.get("OPENAI_MODEL", "gpt-5.2") llm = ChatOpenAI( model=model_name, temperature=0.7, api_key=os.environ.get("OPENAI_API_KEY"), ) # System prompt for the internal researcher researcher_prompt = """You are a Research Specialist. Use internet_search to find information. Return a prose summary of findings. Rules: - Call internet_search ONCE with a focused query - Analyze the returned content - Return a brief summary (2-3 sentences) of key findings - No JSON, no code blocks, just prose""" research_agent = create_deep_agent( model=llm, system_prompt=researcher_prompt, tools=[internet_search_tracked], # Use tracked version # No middleware - this runs in isolated thread ) # Run in isolated thread context - no callback inheritance possible result = research_agent.invoke({"messages": [HumanMessage(content=query)]}) summary = result["messages"][-1].content # Format sources for frontend sources = [ { "url": r["url"], "title": r.get("title", ""), "content": r.get("content", "")[:3000], # Include content preview "status": "found", } for r in search_results if "url" in r and not r.get("error") ] return {"summary": summary, "sources": sources} # Run in thread pool to isolate from parent async context # This blocks the tool execution until research completes, which is acceptable with ThreadPoolExecutor(max_workers=1) as executor: future = executor.submit(_run_research_isolated) result = future.result() # Blocks until complete print(f"[TOOL] research: completed with {len(result['sources'])} sources") return result