外观
概述
本指南演示如何使用 Deep Agents 从零构建一个多步骤网络研究智能体。该智能体将研究问题分解为聚焦的任务,将其委派给专门的子智能体,并将研究结果综合成一份全面的报告。
你将构建的智能体将:
- 使用可选开启的待办事项列表中间件规划研究
- 将聚焦的研究任务委派给具有隔离上下文的子智能体
- 在收集信息的过程中评估搜索结果并规划后续步骤
- 将带适当引用的研究结果综合成最终报告
生成的子智能体将使用 Tavily 进行网络搜索,获取完整的网页内容用于分析。
关键概念
本教程涵盖:
前置条件
需要以下 API 密钥:
环境设置
创建项目目录
bash
mkdir deep-research-agent
cd deep-research-agent安装依赖
Claude
bash
pip install deepagents tavily-python httpx markdownify langchain-anthropic langchain-corebash
uv init
uv add deepagents tavily-python httpx markdownify langchain-anthropic langchain-core
uv syncGemini
bash
pip install deepagents tavily-python httpx markdownify langchain-google-genai langchain-corebash
uv init
uv add deepagents tavily-python httpx markdownify langchain-google-genai langchain-core
uv sync设置 API 密钥
Claude
bash
export ANTHROPIC_API_KEY="your_anthropic_api_key"
export TAVILY_API_KEY="your_tavily_api_key"
export LANGSMITH_API_KEY="your_langsmith_api_key" # OptionalGemini
bash
export GOOGLE_API_KEY="your_google_api_key"
export TAVILY_API_KEY="your_tavily_api_key"
export LANGSMITH_API_KEY="your_langsmith_api_key" # Optional创建项目目录
bash
mkdir deep-research-agent
cd deep-research-agent安装依赖
Claude
bash
npm install deepagents @langchain/anthropic @langchain/coreGemini
bash
npm install deepagents @langchain/google-genai @langchain/core设置 API 密钥
Claude
bash
export ANTHROPIC_API_KEY="your_anthropic_api_key"
export TAVILY_API_KEY="your_tavily_api_key"
export LANGSMITH_API_KEY="your_langsmith_api_key" # OptionalGemini
bash
export GOOGLE_API_KEY="your_google_api_key"
export TAVILY_API_KEY="your_tavily_api_key"
export LANGSMITH_API_KEY="your_langsmith_api_key" # Optional构建智能体
在项目目录中创建 agent.py:
在项目目录中创建 agent.ts:
添加工具
添加自定义搜索工具。tavily_search 工具使用 Tavily 发现 URL,然后获取完整的网页内容,以便智能体可以分析完整的来源而不是摘要。
python
import os
from typing import Annotated, Literal
import httpx
from langchain.tools import InjectedToolArg, tool
from markdownify import markdownify
from tavily import TavilyClient
tavily_client = TavilyClient(api_key=os.environ["TAVILY_API_KEY"])
def fetch_webpage_content(url: str, timeout: float = 10.0) -> str:
"""Fetch webpage and convert HTML to markdown."""
headers = {
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36"
}
try:
response = httpx.get(url, headers=headers, timeout=timeout)
response.raise_for_status()
return markdownify(response.text)
except Exception as e:
return f"Error fetching {url}: {e!s}"
@tool(parse_docstring=True)
def tavily_search(
query: str,
max_results: Annotated[int, InjectedToolArg] = 1,
topic: Annotated[
Literal["general", "news", "finance"], InjectedToolArg
] = "general",
) -> str:
"""Search the web for information on a given query.
Uses Tavily to discover relevant URLs, then fetches and returns full webpage content as markdown.
Args:
query: Search query to execute
max_results: Maximum number of results to return (default: 1)
topic: Topic filter - 'general', 'news', or 'finance' (default: 'general')
Returns:
Formatted search results with full webpage content
"""
search_results = tavily_client.search(
query,
max_results=max_results,
topic=topic,
)
result_texts = []
for result in search_results.get("results", []):
url = result["url"]
title = result["title"]
content = fetch_webpage_content(url)
result_texts.append(f"## {title}\n**URL:** {url}\n\n{content}\n---")
return f"Found {len(result_texts)} result(s) for '{query}':\n\n" + "\n".join(
result_texts
)ts
import { tool } from "langchain";
import { z } from "zod";
async function fetchWebpageContent(
url: string,
timeout = 10_000,
): Promise<string> {
try {
const controller = new AbortController();
const id = setTimeout(() => controller.abort(), timeout);
const response = await fetch(url, {
headers: {
"User-Agent":
"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36",
},
signal: controller.signal,
});
clearTimeout(id);
if (!response.ok) {
return `Error fetching ${url}: HTTP ${response.status}`;
}
return await response.text();
} catch (e) {
return `Error fetching ${url}: ${e}`;
}
}
const tavilySearch = tool(
async ({
query,
maxResults = 1,
topic = "general",
}: {
query: string;
maxResults?: number;
topic?: "general" | "news" | "finance";
}) => {
const response = await fetch("https://api.tavily.com/search", {
method: "POST",
headers: {
"Content-Type": "application/json",
Authorization: `Bearer ${process.env.TAVILY_API_KEY}`,
},
body: JSON.stringify({ query, max_results: maxResults, topic }),
});
const data = (await response.json()) as {
results: Array<{ url: string; title: string }>;
};
const results = data.results ?? [];
const resultTexts: string[] = [];
for (const result of results) {
const content = await fetchWebpageContent(result.url);
resultTexts.push(
`## ${result.title}\n**URL:** ${result.url}\n\n${content}\n---`,
);
}
return (
`Found ${resultTexts.length} result(s) for '${query}':\n\n` +
resultTexts.join("\n")
);
},
{
name: "tavily_search",
description:
"Search the web for information on a given query. Uses Tavily to discover relevant URLs, then fetches and returns full webpage content.",
schema: z.object({
query: z.string().describe("Search query to execute"),
maxResults: z
.number()
.optional()
.default(1)
.describe("Maximum number of results to return (default: 1)"),
topic: z
.enum(["general", "news", "finance"])
.optional()
.default("general")
.describe(
"Topic filter - 'general', 'news', or 'finance' (default: 'general')",
),
}),
},
);添加提示词
将编排器工作流和子智能体提示词模板添加到 agent.py:
将编排器工作流和子智能体提示词模板添加到 agent.ts:
python
RESEARCH_WORKFLOW_INSTRUCTIONS = """# Research Workflow
Follow this workflow for all research requests:
1. **Plan**: Create a todo list with write_todos to break down the research into focused tasks
2. **Save the request**: Use write_file() to save the user's research question to `/research_request.md`
3. **Research**: Delegate research tasks to sub-agents using the task() tool - ALWAYS use sub-agents for research, never conduct research yourself
4. **Synthesize**: Review all sub-agent findings and consolidate citations (each unique URL gets one number across all findings)
5. **Write Report**: Write a comprehensive final report to `/final_report.md` (see Report Writing Guidelines below)
6. **Verify**: Read `/research_request.md` and confirm you've addressed all aspects with proper citations and structure
## Research Planning Guidelines
- Batch similar research tasks into a single TODO to minimize overhead
- For simple fact-finding questions, use 1 sub-agent
- For comparisons or multi-faceted topics, delegate to multiple parallel sub-agents
- Each sub-agent should research one specific aspect and return findings
## Report Writing Guidelines
When writing the final report to `/final_report.md`, follow these structure patterns:
**For comparisons:**
1. Introduction
2. Overview of topic A
3. Overview of topic B
4. Detailed comparison
5. Conclusion
**For lists/rankings:**
Simply list items with details - no introduction needed:
1. Item 1 with explanation
2. Item 2 with explanation
3. Item 3 with explanation
**For summaries/overviews:**
1. Overview of topic
2. Key concept 1
3. Key concept 2
4. Key concept 3
5. Conclusion
**General guidelines:**
- Use clear section headings (## for sections, ### for subsections)
- Write in paragraph form by default - be text-heavy, not just bullet points
- Do NOT use self-referential language ("I found...", "I researched...")
- Write as a professional report without meta-commentary
- Each section should be comprehensive and detailed
- Use bullet points only when listing is more appropriate than prose
**Citation format:**
- Cite sources inline using [1], [2], [3] format
- Assign each unique URL a single citation number across ALL sub-agent findings
- End report with ### Sources section listing each numbered source
- Number sources sequentially without gaps (1,2,3,4...)
- Format: [1] Source Title: URL (each on separate line for proper list rendering)
- Example:
Some important finding [1]. Another key insight [2].
### Sources
[1] AI Research Paper: https://example.com/paper
[2] Industry Analysis: https://example.com/analysis
"""python
RESEARCHER_INSTRUCTIONS = """You are a research assistant conducting research on the user's input topic. For context, today's date is {date}.
Your job is to use tools to gather information about the user's input topic.
You can use the tavily_search tool to find resources that can help answer the research question.
You can call it in series or in parallel, your research is conducted in a tool-calling loop.
You have access to the tavily_search tool for conducting web searches.
Think like a human researcher with limited time. Follow these steps:
1. **Read the question carefully** - What specific information does the user need?
2. **Start with broader searches** - Use broad, comprehensive queries first
3. **After each search, pause and assess** - Do I have enough to answer? What's still missing?
4. **Execute narrower searches as you gather information** - Fill in the gaps
5. **Stop when you can answer confidently** - Don't keep searching for perfection
**Tool Call Budgets** (Prevent excessive searching):
- **Simple queries**: Use 2-3 search tool calls maximum
- **Complex queries**: Use up to 5 search tool calls maximum
- **Always stop**: After 5 search tool calls if you cannot find the right sources
**Stop Immediately When**:
- You can answer the user's question comprehensively
- You have 3+ relevant examples/sources for the question
- Your last 2 searches returned similar information
After each search, assess results before continuing: What key information did I find? What's missing? Do I have enough to answer? Should I search more or provide my answer?
When providing your findings back to the orchestrator:
1. **Structure your response**: Organize findings with clear headings and detailed explanations
2. **Cite sources inline**: Use [1], [2], [3] format when referencing information from your searches
3. **Include Sources section**: End with ### Sources listing each numbered source with title and URL
Example:
## Key Findings
Context engineering is a critical technique for AI agents [1]. Studies show that proper context management can improve performance by 40% [2].
### Sources
[1] Context Engineering Guide: https://example.com/context-guide
[2] AI Performance Study: https://example.com/study
The orchestrator will consolidate citations from all sub-agents into the final report.
"""python
SUBAGENT_DELEGATION_INSTRUCTIONS = """# Sub-Agent Research Coordination
Your role is to coordinate research by delegating tasks from your TODO list to specialized research sub-agents.
## Delegation Strategy
**DEFAULT: Start with 1 sub-agent** for most queries:
- "What is quantum computing?" -> 1 sub-agent (general overview)
- "List the top 10 coffee shops in San Francisco" -> 1 sub-agent
- "Summarize the history of the internet" -> 1 sub-agent
- "Research context engineering for AI agents" -> 1 sub-agent (covers all aspects)
**ONLY parallelize when the query EXPLICITLY requires comparison or has clearly independent aspects:**
**Explicit comparisons** -> 1 sub-agent per element:
- "Compare OpenAI vs Anthropic vs DeepMind AI safety approaches" -> 3 parallel sub-agents
- "Compare Python vs JavaScript for web development" -> 2 parallel sub-agents
**Clearly separated aspects** -> 1 sub-agent per aspect (use sparingly):
- "Research renewable energy adoption in Europe, Asia, and North America" -> 3 parallel sub-agents (geographic separation)
- Only use this pattern when aspects cannot be covered efficiently by a single comprehensive search
## Key Principles
- **Bias towards single sub-agent**: One comprehensive research task is more token-efficient than multiple narrow ones
- **Avoid premature decomposition**: Don't break "research X" into "research X overview", "research X techniques", "research X applications" - just use 1 sub-agent for all of X
- **Parallelize only for clear comparisons**: Use multiple sub-agents when comparing distinct entities or geographically separated data
## Parallel Execution Limits
- Use at most {max_concurrent_research_units} parallel sub-agents per iteration
- Make multiple task() calls in a single response to enable parallel execution
- Each sub-agent returns findings independently
## Research Limits
- Stop after {max_researcher_iterations} delegation rounds if you haven't found adequate sources
- Stop when you have sufficient information to answer comprehensively
- Bias towards focused research over exhaustive exploration"""ts
const RESEARCH_WORKFLOW_INSTRUCTIONS = `# Research Workflow
Follow this workflow for all research requests:
1. **Plan**: Create a todo list with write_todos to break down the research into focused tasks
2. **Save the request**: Use write_file() to save the user's research question to \`/research_request.md\`
3. **Research**: Delegate research tasks to sub-agents using the task() tool - ALWAYS use sub-agents for research, never conduct research yourself
4. **Synthesize**: Review all sub-agent findings and consolidate citations (each unique URL gets one number across all findings)
5. **Write Report**: Write a comprehensive final report to \`/final_report.md\` (see Report Writing Guidelines below)
6. **Verify**: Read \`/research_request.md\` and confirm you've addressed all aspects with proper citations and structure
## Research Planning Guidelines
- Batch similar research tasks into a single TODO to minimize overhead
- For simple fact-finding questions, use 1 sub-agent
- For comparisons or multi-faceted topics, delegate to multiple parallel sub-agents
- Each sub-agent should research one specific aspect and return findings
## Report Writing Guidelines
When writing the final report to \`/final_report.md\`, follow these structure patterns:
**For comparisons:**
1. Introduction
2. Overview of topic A
3. Overview of topic B
4. Detailed comparison
5. Conclusion
**For lists/rankings:**
Simply list items with details - no introduction needed:
1. Item 1 with explanation
2. Item 2 with explanation
3. Item 3 with explanation
**For summaries/overviews:**
1. Overview of topic
2. Key concept 1
3. Key concept 2
4. Key concept 3
5. Conclusion
**General guidelines:**
- Use clear section headings (## for sections, ### for subsections)
- Write in paragraph form by default - be text-heavy, not just bullet points
- Do NOT use self-referential language ("I found...", "I researched...")
- Write as a professional report without meta-commentary
- Each section should be comprehensive and detailed
- Use bullet points only when listing is more appropriate than prose
**Citation format:**
- Cite sources inline using [1], [2], [3] format
- Assign each unique URL a single citation number across ALL sub-agent findings
- End report with ### Sources section listing each numbered source
- Number sources sequentially without gaps (1,2,3,4...)
- Format: [1] Source Title: URL (each on separate line for proper list rendering)
- Example:
Some important finding [1]. Another key insight [2].
### Sources
[1] AI Research Paper: https://example.com/paper
[2] Industry Analysis: https://example.com/analysis
`;ts
const RESEARCHER_INSTRUCTIONS = `You are a research assistant conducting research on the user's input topic. For context, today's date is {date}.
Your job is to use tools to gather information about the user's input topic.
You can use the tavily_search tool to find resources that can help answer the research question.
You can call it in series or in parallel, your research is conducted in a tool-calling loop.
You have access to the tavily_search tool for conducting web searches.
Think like a human researcher with limited time. Follow these steps:
1. **Read the question carefully** - What specific information does the user need?
2. **Start with broader searches** - Use broad, comprehensive queries first
3. **After each search, pause and assess** - Do I have enough to answer? What's still missing?
4. **Execute narrower searches as you gather information** - Fill in the gaps
5. **Stop when you can answer confidently** - Don't keep searching for perfection
**Tool Call Budgets** (Prevent excessive searching):
- **Simple queries**: Use 2-3 search tool calls maximum
- **Complex queries**: Use up to 5 search tool calls maximum
- **Always stop**: After 5 search tool calls if you cannot find the right sources
**Stop Immediately When**:
- You can answer the user's question comprehensively
- You have 3+ relevant examples/sources for the question
- Your last 2 searches returned similar information
After each search, assess results before continuing: What key information did I find? What's missing? Do I have enough to answer? Should I search more or provide my answer?
When providing your findings back to the orchestrator:
1. **Structure your response**: Organize findings with clear headings and detailed explanations
2. **Cite sources inline**: Use [1], [2], [3] format when referencing information from your searches
3. **Include Sources section**: End with ### Sources listing each numbered source with title and URL
Example:
## Key Findings
Context engineering is a critical technique for AI agents [1]. Studies show that proper context management can improve performance by 40% [2].
### Sources
[1] Context Engineering Guide: https://example.com/context-guide
[2] AI Performance Study: https://example.com/study
The orchestrator will consolidate citations from all sub-agents into the final report.
`;ts
const SUBAGENT_DELEGATION_INSTRUCTIONS = `# Sub-Agent Research Coordination
Your role is to coordinate research by delegating tasks from your TODO list to specialized research sub-agents.
## Delegation Strategy
**DEFAULT: Start with 1 sub-agent** for most queries:
- "What is quantum computing?" -> 1 sub-agent (general overview)
- "List the top 10 coffee shops in San Francisco" -> 1 sub-agent
- "Summarize the history of the internet" -> 1 sub-agent
- "Research context engineering for AI agents" -> 1 sub-agent (covers all aspects)
**ONLY parallelize when the query EXPLICITLY requires comparison or has clearly independent aspects:**
**Explicit comparisons** -> 1 sub-agent per element:
- "Compare OpenAI vs Anthropic vs DeepMind AI safety approaches" -> 3 parallel sub-agents
- "Compare Python vs JavaScript for web development" -> 2 parallel sub-agents
**Clearly separated aspects** -> 1 sub-agent per aspect (use sparingly):
- "Research renewable energy adoption in Europe, Asia, and North America" -> 3 parallel sub-agents (geographic separation)
- Only use this pattern when aspects cannot be covered efficiently by a single comprehensive search
## Key Principles
- **Bias towards single sub-agent**: One comprehensive research task is more token-efficient than multiple narrow ones
- **Avoid premature decomposition**: Don't break "research X" into "research X overview", "research X techniques", "research X applications" - just use 1 sub-agent for all of X
- **Parallelize only for clear comparisons**: Use multiple sub-agents when comparing distinct entities or geographically separated data
## Parallel Execution Limits
- Use at most {maxConcurrentResearchUnits} parallel sub-agents per iteration
- Make multiple task() calls in a single response to enable parallel execution
- Each sub-agent returns findings independently
## Research Limits
- Stop after {maxResearcherIterations} delegation rounds if you haven't found adequate sources
- Stop when you have sufficient information to answer comprehensively
- Bias towards focused research over exhaustive exploration`;启用任务规划
任务规划是可选开启的。研究工作流使用 write_todos 将问题分解为聚焦的任务,因此在创建智能体时请传入 TodoListMiddleware。
python
from langchain.agents.middleware import TodoListMiddlewaretypescript
import { todoListMiddleware } from "langchain";在下一步创建智能体时,你需要包含此中间件。
创建智能体
将模型初始化和智能体创建代码添加到 agent.py。选择你的提供商。包含 TodoListMiddleware,以便规划工具可用:
Claude
python
from datetime import datetime
from deepagents import create_deep_agent
from langchain.agents.middleware import TodoListMiddleware
from langchain.chat_models import init_chat_model
max_concurrent_research_units = 3
max_researcher_iterations = 3
current_date = datetime.now().strftime("%Y-%m-%d")
INSTRUCTIONS = (
RESEARCH_WORKFLOW_INSTRUCTIONS
+ "\n\n"
+ "=" * 80
+ "\n\n"
+ SUBAGENT_DELEGATION_INSTRUCTIONS.format(
max_concurrent_research_units=max_concurrent_research_units,
max_researcher_iterations=max_researcher_iterations,
)
)
research_sub_agent = {
"name": "research-agent",
"description": "Delegate research to the sub-agent. Give one topic at a time.",
"system_prompt": RESEARCHER_INSTRUCTIONS.format(date=current_date),
"tools": [tavily_search],
}
model = init_chat_model(model="anthropic:claude-sonnet-4-5-20250929", temperature=0.0)
agent = create_deep_agent(
model=model,
tools=[tavily_search],
system_prompt=INSTRUCTIONS,
subagents=[research_sub_agent],
middleware=[TodoListMiddleware()],
)Gemini
python
from datetime import datetime
from deepagents import create_deep_agent
from langchain.agents.middleware import TodoListMiddleware
from langchain_google_genai import ChatGoogleGenerativeAI
max_concurrent_research_units = 3
max_researcher_iterations = 3
current_date = datetime.now().strftime("%Y-%m-%d")
INSTRUCTIONS = (
RESEARCH_WORKFLOW_INSTRUCTIONS
+ "\n\n"
+ "=" * 80
+ "\n\n"
+ SUBAGENT_DELEGATION_INSTRUCTIONS.format(
max_concurrent_research_units=max_concurrent_research_units,
max_researcher_iterations=max_researcher_iterations,
)
)
research_sub_agent = {
"name": "research-agent",
"description": "Delegate research to the sub-agent. Give one topic at a time.",
"system_prompt": RESEARCHER_INSTRUCTIONS.format(date=current_date),
"tools": [tavily_search],
}
model = ChatGoogleGenerativeAI(model="gemini-3-pro-preview", temperature=0.0)
agent = create_deep_agent(
model=model,
tools=[tavily_search],
system_prompt=INSTRUCTIONS,
subagents=[research_sub_agent],
middleware=[TodoListMiddleware()],
)将模型初始化和智能体创建代码添加到 agent.ts。包含 todoListMiddleware,以便规划工具可用:
ts
import { createDeepAgent } from "deepagents";
import { ChatAnthropic } from "@langchain/anthropic";
import { todoListMiddleware } from "langchain";
const maxConcurrentResearchUnits = 3;
const maxResearcherIterations = 3;
const currentDate = new Date().toISOString().split("T")[0];
const INSTRUCTIONS =
RESEARCH_WORKFLOW_INSTRUCTIONS +
"\n\n" +
"=".repeat(80) +
"\n\n" +
SUBAGENT_DELEGATION_INSTRUCTIONS.replace(
"{maxConcurrentResearchUnits}",
String(maxConcurrentResearchUnits),
).replace("{maxResearcherIterations}", String(maxResearcherIterations));
const researchSubAgent = {
name: "research-agent",
description: "Delegate research to the sub-agent. Give one topic at a time.",
systemPrompt: RESEARCHER_INSTRUCTIONS.replace("{date}", currentDate),
tools: [tavilySearch],
};
const model = new ChatAnthropic({
model: "claude-sonnet-4-5-20250929",
temperature: 0,
});
const agent = await createDeepAgent({
model,
tools: [tavilySearch],
systemPrompt: INSTRUCTIONS,
subagents: [researchSubAgent],
middleware: [todoListMiddleware()],
});运行智能体
你可以同步运行智能体,即它会等待完整结果然后打印出来,也可以在更新到来时进行流式输出。
将相应选项卡中的代码添加到 agent.py 末尾:
将相应选项卡中的代码添加到 agent.ts 末尾:
同步运行
python
from langchain.messages import HumanMessage
if __name__ == "__main__":
result = agent.invoke(
{
"messages": [
HumanMessage(
content="What are the main differences between RAG and fine-tuning for LLM applications?"
)
]
}
)
for msg in result.get("messages", []):
if hasattr(msg, "content") and msg.content:
print(msg.content)ts
{
async function main() {
const result = await agent.invoke({
messages: [
{
role: "user",
content:
"What are the main differences between RAG and fine-tuning for LLM applications?",
},
],
});
for (const msg of result.messages ?? []) {
if (msg.content) {
console.log(msg.content);
}
}
}
main().catch((err) => {
console.error(err);
process.exitCode = 1;
});
}流式输出更新
python
from langchain.messages import HumanMessage
if __name__ == "__main__":
stream = agent.stream_events(
{
"messages": [
HumanMessage(content="Compare Python vs JavaScript for web development")
]
},
version="v3",
)
for message in stream.messages:
for token in message.text:
print(token, end="", flush=True)ts
{
async function main() {
const stream = await agent.streamEvents(
{
messages: [
{
role: "user",
content: "Compare Python vs JavaScript for web development",
},
],
},
{ version: "v3" },
);
for await (const message of stream.messages) {
for await (const token of message.text) {
process.stdout.write(token);
}
}
}
main().catch((err) => {
console.error(err);
process.exitCode = 1;
});
}从项目根目录运行智能体:
sh
python agent.pysh
npx tsx agent.ts如果在运行前设置了 LANGSMITH_API_KEY 环境变量,你可以在 LangSmith 中查看智能体的追踪,以调试和监控多步骤行为。
完整代码
在 GitHub 上查看完整的深度研究示例。
后续步骤
既然你已经构建了智能体,可以通过更改智能体文件中的提示词常量来自定义它,以调整工作流、委派策略或研究员行为。 你还可以调整委派限制,以允许更多的并行子智能体或委派轮次。
有关本教程中概念的更多信息,请查看以下资源: