[ ABORT TO HUD ]
SEQ. 1

Native Search Integration

🔍 Web Search Tool⏱ 20 min⭐ 600 BASE XP⌨ HANDS-ON LAB

First-Party Web Search Tool

Anthropic provides a built-in Web Search Tool (web_search_20250305) that allows Claude to search the public internet dynamically when responding to queries requiring real-time information.

API Configuration

const response = await anthropic.messages.create({
  model: "claude-3-7-sonnet-20250219",
  max_tokens: 4096,
  tools: [{
    type: "web_search_20250305",
    name: "web_search",
    max_uses: 5,
    allowed_domains: ["docs.anthropic.com", "github.com"]
  }],
  messages: [{ role: "user", content: "What are the latest Claude 3.7 Sonnet features?" }]
});

Domain Governance

Enterprise applications can constrain the search space using allowed_domains (allowlist) and blocked_domains (denylist) to ensure content is retrieved only from verified knowledge sources.

⌨ HANDS-ON LABGive Claude Live Web Access
⭐ +200 XP

Your model's knowledge has a cutoff - the news doesn't. Enable the server-side web_search tool with curl, then lock it down to a single trusted domain.

1Call /v1/messages with the web_search tool in the tools array.
2Re-run the request restricted to a single trusted domain with allowed_domains.
lab-sandbox — simulated environment
INFINITY LAB SANDBOX v2.6 — simulated shell
Type the command for the current objective. Helpers: "hint", "solution", "clear".
$
OBJECTIVE 1 / 2 — type "hint" if stuck
SYNAPSE VERIFICATION
QUERY 1 // 2
How is the built-in web search tool enabled in the Messages API?
By passing an external MCP URL
By adding the built-in tool object with type web_search_20250305 to the tools array
By adding 'search: true' to the system prompt
By setting temperature to 0