# 🚀 Deep Research

## 🚀 Quickstart

**Prerequisites**: Install [uv](https://docs.astral.sh/uv/) package manager:

```bash
curl -LsSf https://astral.sh/uv/install.sh | sh
```

Ensure you are in the `deep_research` directory:

```bash
cd examples/deep_research
```

Install packages:

```bash
uv sync
```

Set your API keys in your environment:

```bash
export ANTHROPIC_API_KEY=your_anthropic_api_key_here  # Required for Claude model
export GOOGLE_API_KEY=your_google_api_key_here        # Required for Gemini model ([get one here](https://ai.google.dev/gemini-api/docs))
export TAVILY_API_KEY=your_tavily_api_key_here        # Required for web search ([get one here](https://www.tavily.com/)) with a generous free tier
export LANGSMITH_API_KEY=your_langsmith_api_key_here  # [LangSmith API key](https://smith.langchain.com/settings) (free to sign up)
```

## Usage Options

You can run this example in two ways:

### Option 1: Jupyter Notebook

Run the interactive notebook to step through the research agent:

```bash
uv run jupyter notebook research_agent.ipynb
```

### Option 2: LangGraph Server

Run a local [LangGraph server](https://langchain-ai.github.io/langgraph/tutorials/langgraph-platform/local-server/) with a web interface:

```bash
langgraph dev
```

LangGraph server will open a new browser window with the Studio interface, which you can submit your search query to:

<img width="2869" height="1512" alt="Screenshot 2025-11-17 at 11 42 59 AM" src="https://github.com/user-attachments/assets/03090057-c199-42fe-a0f7-769704c2124b" />

You can also connect the LangGraph server to a [UI specifically designed for deepagents](https://github.com/langchain-ai/deep-agents-ui):

```bash
git clone https://github.com/langchain-ai/deep-agents-ui.git
cd deep-agents-ui
yarn install
yarn dev
```

Then follow the instructions in the [deep-agents-ui README](https://github.com/langchain-ai/deep-agents-ui?tab=readme-ov-file#connecting-to-a-langgraph-server) to connect the UI to the running LangGraph server.

This provides a user-friendly chat interface and visualization of files in state.

<img width="2039" height="1495" alt="Screenshot 2025-11-17 at 1 11 27 PM" src="https://github.com/user-attachments/assets/d559876b-4c90-46fb-8e70-c16c93793fa8" />

## 📚 Resources

- **[Deep Research Course](https://academy.langchain.com/courses/deep-research-with-langgraph)** - Full course on deep research with LangGraph

### Custom Model

By default, `deepagents` uses `"claude-sonnet-4-5-20250929"`. You can customize this by passing any [LangChain model object](https://python.langchain.com/docs/integrations/chat/). See the Deep Agents package [README](https://github.com/langchain-ai/deepagents?tab=readme-ov-file#model) for more details.

```python
from langchain.chat_models import init_chat_model
from deepagents import create_deep_agent

# Using Claude
model = init_chat_model(model="anthropic:claude-sonnet-4-5-20250929", temperature=0.0)

# Using Gemini
from langchain_google_genai import ChatGoogleGenerativeAI
model = ChatGoogleGenerativeAI(model="gemini-3-pro-preview")

agent = create_deep_agent(
    model=model,
)
```

### Custom Instructions

The deep research agent uses custom instructions defined in `research_agent/prompts.py` that complement (rather than duplicate) the default middleware instructions. You can modify these in any way you want.

| Instruction Set | Purpose |
|----------------|---------|
| `RESEARCH_WORKFLOW_INSTRUCTIONS` | Defines the 5-step research workflow: save request → plan with TODOs → delegate to sub-agents → synthesize → respond. Includes research-specific planning guidelines like batching similar tasks and scaling rules for different query types. |
| `SUBAGENT_DELEGATION_INSTRUCTIONS` | Provides concrete delegation strategies with examples: simple queries use 1 sub-agent, comparisons use 1 per element, multi-faceted research uses 1 per aspect. Sets limits on parallel execution (max 3 concurrent) and iteration rounds (max 3). |
| `RESEARCHER_INSTRUCTIONS` | Guides individual research sub-agents to conduct focused web searches. Includes hard limits (2-3 searches for simple queries, max 5 for complex), emphasizes using `think_tool` after each search for strategic reflection, and defines stopping criteria. |

### Custom Tools

The deep research agent adds the following custom tools beyond the built-in deepagent tools. You can also use your own tools, including via MCP servers. See the Deep Agents package [README](https://github.com/langchain-ai/deepagents?tab=readme-ov-file#mcp) for more details.

| Tool Name | Description |
|-----------|-------------|
| `tavily_search` | Web search tool that uses Tavily purely as a URL discovery engine. Performs searches using Tavily API to find relevant URLs, fetches full webpage content via HTTP with proper User-Agent headers (avoiding 403 errors), converts HTML to markdown, and returns the complete content without summarization to preserve all information for the agent's analysis. Works with both Claude and Gemini models. |
| `think_tool` | Strategic reflection mechanism that helps the agent pause and assess progress between searches, analyze findings, identify gaps, and plan next steps. |
