@trishchuk/mcp-fetch-server

A high-performance Model Context Protocol (MCP) server providing an anti-bot-resilient fetch tool for AI agents (Claude Code, Claude Desktop, Cursor, Windsurf, Cline, Antigravity, etc.).

Powered by @trishchuk/fetch — a native curl-impersonate-style HTTP client that accurately mimics real browser TLS (JA3/JA4, ClientHello) and HTTP/2 fingerprints.

🚀 Why this server?

Standard Node.js/Undici HTTP clients get immediately flagged and blocked by modern bot-protection systems (Cloudflare Turnstile / Under Attack Mode, DataDome, PerimeterX / HUMAN, Akamai, Kasada, AWS WAF).

Furthermore, standard MCP fetching tools often fail on large payloads or blow up LLM token contexts.

@trishchuk/mcp-fetch-server solves both problems:

1. Realistic Browser Impersonation: Replicates exact cipher suites, TLS extensions, ALPN order, and HTTP/2 settings frames from modern browsers (Chrome, Safari, Firefox).
2. LLM Context-Safe Truncation: Streams and caps response bodies at 2MB (maxResponseBytes). Oversized pages are cleanly truncated and flagged with "truncated": true rather than crashing with errors.
3. Stateful Sessions: Maintain cookies, login states, and connection pools across multiple agent tool calls using the session parameter.
4. Smart Encoding: Automatically detects MIME types and returns clean UTF-8 text for HTML/JSON/XML or Base64 for binary files (images, PDFs, documents).

✅ Requirements

• Node.js >= 24 — required by @trishchuk/fetch.
• Prebuilt native binaries ship for macOS (arm64, x64), Linux (x64/arm64, glibc and musl) and Windows (x64). Other platforms are not supported by the underlying client.

📦 Installation & Setup

Option 1: Run with npx (No installation needed)

You can run the server directly via npx:

npx -y @trishchuk/mcp-fetch-server

Option 2: Global or Local Installation

# Global
npm install -g @trishchuk/mcp-fetch-server

# Or clone & install locally
git clone https://github.com/x51xxx/mcp-fetch-server.git
cd mcp-fetch-server
npm install

⚙️ MCP Client Configuration

Claude Code

Add directly via CLI:

# Using npx (recommended)
claude mcp add fetch -- npx -y @trishchuk/mcp-fetch-server

# Or using local path
claude mcp add fetch -- node /path/to/mcp-fetch-server/src/index.js

Claude Desktop

Add to your claude_desktop_config.json:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "fetch": {
      "command": "npx",
      "args": ["-y", "@trishchuk/mcp-fetch-server"]
    }
  }
}

Cursor / Windsurf / Antigravity (.mcp.json)

Create or update .mcp.json in your workspace:

{
  "mcpServers": {
    "fetch": {
      "command": "npx",
      "args": ["-y", "@trishchuk/mcp-fetch-server"]
    }
  }
}

🛠️ Tool Reference: fetch

Input Parameters

| Parameter | Type | Default | Description | | :--- | :--- | :--- | :--- | | url | string | required | Target absolute URL (e.g. https://example.com/api). | | method | string | "GET" | HTTP method (GET, POST, PUT, DELETE, PATCH, HEAD, etc.). | | headers | object | undefined | Request headers as key-value pairs ({"Authorization": "Bearer ..."}). | | body | string | undefined | Request body sent as UTF-8 string (JSON, form-encoded, raw text). | | impersonate | string | "chrome_147" | Browser fingerprint preset (e.g. "chrome_147", "safari_26", "random"). | | platform | string | undefined | Declared OS: "windows", "macos", "linux", "android", or "ios". | | proxy | string | undefined | Proxy URL: http://, https://, or socks5:// (supports user:pass@host:port). | | session | string | undefined | Session ID for sharing client connections and cookie jars across multiple calls. | | resolve | object | undefined | Custom DNS pinning (e.g. {"example.com": "1.2.3.4"}). SSRF-safe testing. | | redirect | string | "follow" | Redirect mode: "follow", "manual", or "error". | | httpVersion | string | undefined | Force protocol version: "http1" or "http2". | | tlsMinVersion | string | undefined | Minimum TLS version: "1.0", "1.1", "1.2", "1.3". | | tlsMaxVersion | string | undefined | Maximum TLS version: "1.0", "1.1", "1.2", "1.3". | | timeoutMs | number | undefined | Overall request timeout in milliseconds. | | maxResponseBytes| number | 2097152 | Body limit in bytes (max 2MB). Responses exceeding this are safely truncated. | | encoding | string | "auto" | Body return format: "auto" (text for textual MIME types, base64 for binary), "text", or "base64". |

Response Schemas

1. Successful HTTP Exchange

Any completed HTTP transfer returns a standard JSON result (including 404, 500, or 3xx under redirect: "manual"):

{
  "status": 200,
  "statusText": "OK",
  "ok": true,
  "url": "https://example.com/data",
  "redirected": false,
  "headers": {
    "content-type": "application/json; charset=utf-8",
    "cache-control": "max-age=3600"
  },
  "bodyEncoding": "text",
  "body": "{\"message\": \"Hello world\"}",
  "truncated": false
}

2. Network / Transport Failure

If the network connection fails, times out, or the URL is invalid, the tool returns isError: true:

{
  "error": true,
  "code": "TIMEOUT",
  "message": "failed to read response body: request or response body error: operation timed out"
}

💡 Usage Examples for Agents

1. Bypass Bot Detection on Protected Target

{
  "url": "https://protected-site.com/products",
  "impersonate": "chrome_147",
  "platform": "macos",
  "headers": {
    "Accept-Language": "en-US,en;q=0.9"
  }
}

2. Multi-Step Scraping with Persistent Session (Cookie Jar)

// Step 1: Login / Obtain Session Cookie
{
  "url": "https://example.com/api/login",
  "method": "POST",
  "session": "agent-crawler-01",
  "headers": { "Content-Type": "application/json" },
  "body": "{\"user\":\"admin\",\"password\":\"secret\"}"
}

// Step 2: Access protected resource (session cookies automatically preserved)
{
  "url": "https://example.com/api/dashboard",
  "session": "agent-crawler-01"
}

3. Route Through a SOCKS5 Proxy

{
  "url": "https://geo-restricted.example.com",
  "proxy": "socks5://user:[email protected]:1080",
  "impersonate": "safari_26"
}

4. Fetching Binary Assets (Images, PDFs)

{
  "url": "https://example.com/report.pdf",
  "encoding": "base64"
}

5. DNS Pinning for SSRF-Safe Ingestion

{
  "url": "https://internal-origin.example.com/feed",
  "resolve": {
    "internal-origin.example.com": "192.0.2.42"
  },
  "redirect": "manual"
}

🔬 Impersonation Presets & Fingerprints

@trishchuk/mcp-fetch-server supports a wide range of browser fingerprints:

• Chrome: "chrome_100" … "chrome_149" (e.g. "chrome_147", "chrome_131", "chrome_116")
• Edge: "edge_101" … "edge_148"
• Opera: "opera_116" … "opera_131"
• Firefox: "firefox_109", "firefox_133", "firefox_147" …, plus "firefox_private_136" and "firefox_android_135"
• Safari: "safari_15.3" … "safari_26.4", plus iOS/iPad variants ("safari_ios_26", "safari_ipad_26")
• OkHttp (Android apps): "okhttp_3.9" … "okhttp_5"
• Dynamic: "random", "weighted_random" (rotates fingerprints automatically, pinned per session)

Version numbers use underscores (chrome_147, not chrome147). An unknown name fails fast with an InvalidArg error that lists every accepted variant.

🧪 Development

npm install
npm start          # run the server over stdio
npm test           # end-to-end smoke tests, no network required
npm run format     # format with Biome
npm run lint       # lint with Biome
npm run check      # format + lint check, also run before publish

The tests spawn the real server over stdio and drive it with an MCP client against a local HTTP server, covering truncation at the cap, redirect modes, HEAD, base64 bodies, timeouts and transport errors.

📄 License

MIT © Taras Trishchuk