Wikipedia MCP Server

A Model Context Protocol (MCP) server that provides comprehensive Wikipedia access for AI assistants. Built in TypeScript, deployed on Vercel, and fully compatible with the MCP Streamable HTTP transport (protocol version 2025-03-26).

Features

• 🔍 Advanced Search — find articles with relevance ranking
• 📄 Full Article Access — plain text extracts or complete wikitext
• 📝 Smart Summaries — concise summaries tailored to a specific query
• 🗂️ Section Analysis — extract and summarize individual sections
• 🔗 Link Discovery — internal links and related articles
• 🌍 Multi-language — 50+ language codes, 140+ country codes, resolved automatically
• 🔀 Parallel Search — multi_search_wikipedia runs multiple queries simultaneously
• 🎯 Fact Extraction — structured key-fact lists from any article
• 📍 Coordinates — lat/lon for geographic articles
• ⚡ Streamable HTTP — full MCP transport support (POST + GET SSE + DELETE)
• 🔒 Security hardened — input sanitization, tiered rate limiting, no Server header
• 🚀 Vercel ready — stateless serverless deployment, zero cold-start friction

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Quick Start

1. Deploy

git clone https://github.com/YOUR_USERNAME/wikipedia-mcp-vercel.git
cd wikipedia-mcp-vercel
vercel

Or use the Deploy with Vercel button above.

2. Connect your AI client

The server implements MCP Streamable HTTP transport (2025-03-26).
Both the POST channel (client → server) and the GET SSE channel (server → client) are supported.

MCP endpoint: https://your-app.vercel.app/mcp

Claude Desktop

{
  "mcpServers": {
    "wikipedia": {
      "type": "http",
      "url": "https://your-app.vercel.app/mcp"
    }
  }
}

Claude Code / CLI

claude mcp add wikipedia --transport http https://your-app.vercel.app/mcp

Any MCP client (generic)

Configure the client with transport type streamable-http and the endpoint URL above.
The server uses stateless mode (no Mcp-Session-Id header), which is correct and expected for serverless deployments.

3. Environment variables (optional)

Variable	Default	Description
WIKIPEDIA_LANGUAGE	en	Wikipedia language code (e.g. ja, es, de)
WIKIPEDIA_COUNTRY	US	Country code → language mapping (e.g. JP, CN, LK)
ENABLE_CACHE	false	In-memory cache (useful for local dev)
WIKIPEDIA_BOT_USERNAME	—	Bot account username (Account@BotName)
WIKIPEDIA_BOT_PASSWORD	—	Bot account password
PORT	8000	Local dev port (ignored by Vercel)

Copy .env.example → .env for local development.

4. Verify

# Health check
curl https://your-app.vercel.app/health

# Test MCP initialize
curl -X POST https://your-app.vercel.app/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}}}'

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MCP Tools

All 13 tools accept optional language (e.g. "ja") and country (e.g. "JP") parameters. When set, the query is sent as-is to that language's Wikipedia endpoint (e.g. ja.wikipedia.org). Wikipedia's own search can often match a short English title phrase to the correct local article, but there is no translation layer in this server.

Tool reference

Tool	Description
search_wikipedia	Search by keyword in one language
multi_search_wikipedia	Run multiple searches across multiple languages in parallel
get_article	Full article — plain text extract, or wikitext with full: true
get_summary	Introductory summary only
get_sections	Table of contents (section titles + levels)
get_links	All internal wikilinks in an article
get_coordinates	Latitude/longitude for geographic articles
get_related_topics	Related articles via link graph
summarize_article_for_query	Summary focused on a specific question
summarize_article_section	Summary of one named section
extract_key_facts	Bullet-list of key facts
test_wikipedia_connectivity	API diagnostics + auth status
list_supported_countries	All supported language and country codes

MCP Prompts

Three prompt templates are registered and available via prompts/list / prompts/get:

Prompt	Description
search_in_native_language	Query format guidance for non-English Wikipedia
wikipedia_usage_guide	Full guide covering all tools and best practices
multilingual_research	Step-by-step guide for cross-language research

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REST API

Standard HTTP endpoints for non-MCP usage:

GET  /health
GET  /search/:query?limit=10
GET  /article/:title
GET  /summary/:title
GET  /sections/:title
GET  /links/:title
GET  /coordinates/:title
GET  /related/:title?limit=10
GET  /summary/:title/query/:query/length/:maxLength
GET  /summary/:title/section/:section/length/:maxLength
GET  /facts/:title?topic=...&count=5
GET  /test-connectivity
GET  /supported-countries
POST /tools/:toolName

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Architecture

src/
├── server.ts               # Express app wiring
├── routes/
│   ├── mcp.ts              # Streamable HTTP transport (POST + GET SSE + DELETE)
│   └── rest.ts             # REST endpoints
├── mcp-server.ts           # MCPServer helper — tool dispatch, language routing
├── handlers.ts             # Tool handler functions
├── toolRegistrations.ts    # SDK tool + prompt registration
├── toolDefinitions.ts      # JSON Schema definitions (for REST /mcp info)
├── prompts.ts              # Prompt template logic
├── wikipedia-client.ts     # Wikipedia Action API client
├── sanitize.ts             # Input sanitization
├── middleware.ts           # Rate limiting, Server header removal
├── utils.ts                # Shared helpers
└── types.ts                # TypeScript interfaces

Transport design

The server uses stateless Streamable HTTP — the correct mode for serverless platforms:

• POST /mcp — receives JSON-RPC messages, returns JSON or SSE stream
• GET /mcp — opens an SSE channel for server-initiated messages (clients reconnect on timeout)
• DELETE /mcp — session termination (acknowledged; no server-side sessions to clean up)

A fresh McpServer + StreamableHTTPServerTransport instance is created for each request. All Wikipedia logic is handled by the shared, stateless MCPServer helper.

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Development

npm install
npm run dev       # tsx watch mode on port 8000
npm run build     # tsc → dist/
npm start         # node dist/server.js
vercel dev        # local Vercel simulation

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Bot authentication

For higher Wikipedia API rate limits, create a bot password:

1. Log in to your Wikipedia account
2. Go to Special:BotPasswords
3. Create a new bot password
4. Set WIKIPEDIA_BOT_USERNAME=YourAccount@BotName and WIKIPEDIA_BOT_PASSWORD=...

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License

MIT