MCP Web Search Server

MCP server for web search with results optimized for LLMs and advanced bot-detection evasion.

Features

• Search: DuckDuckGo (no API key), Serper.dev, Bing Web Search

• Search aggregation: fallback mode or merge mode that queries multiple providers in parallel, deduplicates and ranks results by query relevance

• Content extraction: Headless browser with stealth injection, browser page pool, and plain HTTP text fallback when pages are blocked

• Anti-detection: Dynamic fingerprint generation (viewport, UA, locale, timezone), human-like behavior, proxy support

• LLM formatting: Clean markdown via Turndown, metadata, structured data, links, images, PDF text extraction

• OCR: Extract text from image URLs using tesseract.js

• Broken link checker: Scan a page and report the status of its outgoing links

• Robustness: Retry with exponential backoff, circuit breaker per provider, token-bucket rate limiting, concurrency limiting, in-flight request deduplication, persistent cache, graceful shutdown

• Observability: Structured JSON logging via Pino, latency/error metrics per provider and fetch operation

• Config hot reload: .env changes are picked up automatically while the server is running

• Multiple transports: stdio (default) or HTTP Streamable MCP transport

Related MCP server: websearch-skill

Installation

npm install
npm run build

Configuration

Copy .env.example to .env and configure:

# Search providers (optional — DuckDuckGo works without API keys)
SERPER_API_KEY=your_key
BING_API_KEY=your_key

# Search aggregation: "fallback" or "merge"
SEARCH_MERGE_MODE=fallback

# Rate limits (requests per second per provider)
SERPER_RATE_LIMIT=10
BING_RATE_LIMIT=10
DUCKDUCKGO_RATE_LIMIT=1

# Anti-detect
STEALTH_ENABLED=true
HEADLESS=true
PROXY_LIST=http://proxy1:8080,http://proxy2:8080
USER_DATA_DIR=

# Browser page pool size
BROWSER_POOL_SIZE=2

# Limits
MAX_RESULTS=10
MAX_CONTENT_LENGTH=8000
MAX_RESPONSE_SIZE_BYTES=10000000
REQUEST_TIMEOUT=30000
CACHE_TTL=300

# Behavior
MIN_DELAY=500
MAX_DELAY=3000
MAX_CONCURRENT=2
SCROLL_TO_BOTTOM=true

# Fetch fallback when the browser is blocked
TEXT_FETCH_FALLBACK=true

# Optional persistent cache directory
CACHE_DIR=./cache

# Logging
LOG_LEVEL=info

# Transport: stdio or http
MCP_TRANSPORT=stdio
HTTP_HOST=127.0.0.1
HTTP_PORT=8080

# Ethics / safety
ROBOTS_TXT_ENABLED=true
ALLOWED_DOMAINS=
BLOCKED_DOMAINS=

# Debug only — weakens browser security
ALLOW_INSECURE_BROWSER_FLAGS=false

MCP Tools

web_search

Search by query.

{
  "query": "latest AI developments 2025",
  "num_results": 10,
  "provider": "auto",
  "recency_days": 7
}

fetch_url

Fetch and clean a page.

{
  "url": "https://example.com/article",
  "max_length": 8000,
  "include_images": false,
  "include_links": false
}

search_and_fetch

Search and automatically fetch top-N results.

{
  "query": "quantum computing breakthrough",
  "num_results": 5,
  "fetch_content": true,
  "max_content_length": 5000,
  "include_images": false,
  "include_links": false
}

health_check

Check provider availability, circuit breaker state, and rate limits.

{}

ocr_image

Extract text from an image URL.

{
  "url": "https://example.com/screenshot.png",
  "language": "eng"
}

check_links

Fetch a page and check its outgoing links.

{
  "url": "https://example.com/article",
  "max_links": 20
}

Claude Desktop Integration

{
  "mcpServers": {
    "web-search": {
      "command": "node",
      "args": ["C:\\Files\\git\\mcp-web-search\\dist\\index.js"],
      "env": {
        "SERPER_API_KEY": "..."
      }
    }
  }
}

HTTP Transport

Set MCP_TRANSPORT=http and HTTP_PORT=8080, then point an MCP client that supports Streamable HTTP at http://127.0.0.1:8080.

Anti-Detection & Reliability

The server uses a layered approach:

1. puppeteer-extra-plugin-stealth — hides automation fingerprints

2. Dynamic fingerprint generation — random Chrome on Windows/macOS/Linux with matching timezone

3. Browser page pool — reusable Puppeteer pages to reduce launch overhead

4. Human-like behavior — random delays, scroll, mouse events

5. Proxy support — random proxy selection from PROXY_LIST

6. Text fetch fallback — plain HTTP fetch when the headless browser is blocked

7. Search result merging & ranking — combine multiple providers and rank by relevance

8. Circuit breaker — temporarily disables failing providers

9. Token-bucket rate limiting — per-provider rate limiting

10. Retry & concurrency limiting — exponential backoff, bounded parallelism, in-flight deduplication

11. Graceful shutdown — waits for active requests on SIGINT/SIGTERM

12. Robots.txt respect — honors site crawl rules (can be disabled)

Development

npm run dev          # watch mode
npm test             # run unit tests
npm run build        # compile TypeScript
npm run lint         # run ESLint
npm run format       # format with Prettier

Docker

docker build -t mcp-web-search .
docker run --rm -e SERPER_API_KEY=... mcp-web-search

License

MIT