1. What Are Tools, Really?
Standard language models are limited by their training cutoff. Tools extend model capabilities beyond raw text generation by providing real-time external access to live web searches, web page fetching, deterministic calculation, and remote API execution.
2. Built-in Tools
Keyless live search utilizing a robust relay cascade (Jina AI, AllOrigins, DuckDuckGo Lite, SearXNG, Hacker News Algolia) with Wikipedia API fallback.
Fetches and strips HTML from external URLs, delivering clean markdown or plain text directly into the agent context window.
Evaluates arithmetic expressions with exact mathematical precision, eliminating arithmetic hallucination.
3. Visual Tool Indicators in Chat
When an agent invokes a tool call, the chat bubble displays a animated indicator ("Searching the web..." or "Processing requested tool..."). Tool call outputs are processed in the background and injected seamlessly into the reasoning pipeline.
4. External MCP Servers (Model Context Protocol)
Connect any remote or local service speaking Anthropic's open Model Context Protocol standard:
Supported MCP Transport Types:
- HTTP / Streamable:
http://localhost:3001/mcp - Server-Sent Events (SSE):
http://localhost:3001/sse - WebSocket:
ws://localhost:3001
Connect servers via Settings → MCP Tools & Servers to instantly expose custom database queries, local file operations, or API triggers to AI agents.
5. System Prompt Tool Injection
When tools are enabled, available tools across all connected servers are merged and injected into the model system prompt. The model outputs structured JSON tool blocks when external data is required.
6. Security & Isolation Controls
Untrusted Content Shield: All external web content is tagged with protective boundaries to prevent prompt injection attacks.
Private IP SSRF Protection: Web fetch proxying explicitly blocks requests to private IP ranges (10.x, 192.168.x, 127.0.0.1) to safeguard local networks.
7. Best Practices for Prompting Tools
Web Search: Include clear time qualifiers (e.g. "Search the web for Gemini 3.6 Flash pricing as of 2026").
Web Fetch: Provide complete URLs including https:// protocol headers.
MCP Integrations: Use clear, descriptive names for your custom MCP tools and servers so agents understand when to invoke them.
8. Tools Troubleshooting
Search Disabled? Toggle Built-In Web Search Cascade back on in Settings → MCP Tools & Servers.
MCP Connection Failed? Ensure your local MCP server has CORS headers enabled for browser cross-origin requests.