Summary
This is part of xpay's pay-per-call MCP ecosystem, bundling 30+ academic research tools behind a single $0.01 USDC per call endpoint. You get Semantic Scholar for citation graphs, arXiv and bioRxiv for preprints, PubMed for medical literature, CrossRef for DOI lookups, and IACR for cryptography papers. No need to juggle multiple API keys or subscriptions. You connect via streamable HTTP, load credits into your xpay wallet on Base, and your MCP client discovers the tools automatically. Useful if you're building research agents or literature review workflows and want instant access to major academic databases without the usual API registration overhead.
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Integrate web data into your AI product. One API to scrape website & brand data.
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xpay MCP Server
980+ AI tools available as MCP servers. Pay $0.01/call in USDC via the x402 protocol. One API key, 30+ providers — no individual provider accounts or subscriptions needed.
Quick Start
1. Get your API key
Sign up at app.xpay.sh and create an API key. Add credits to your wallet (USDC on Base).
2. Add to your MCP client
Claude Desktop / Cursor / Windsurf — add to your MCP config:
{
"mcpServers": {
"xpay": {
"url": "https://mcp.xpay.sh/mcp?key=YOUR_API_KEY"
}
}
}
Claude Code CLI:
claude mcp add --transport http "xpay" "https://mcp.xpay.sh/mcp?key=YOUR_API_KEY"
Replace YOUR_API_KEY with your key from step 1.
3. Use tools
Your AI assistant will automatically discover all available tools. Each tool call costs $0.01 USDC, deducted from your wallet balance.
Collection Servers
Instead of connecting to all 980+ tools, you can connect to a focused collection:
| Collection | Endpoint | Tools | Providers |
|---|---|---|---|
| All Tools | https://mcp.xpay.sh/mcp?key=YOUR_API_KEY | 980+ | All 30+ |
| Lead Generation | https://lead-gen.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~50 | Hunter, Apollo, Tomba, Sixtyfour, Fiber, Exa, Nyne |
| Competitive Intel | https://compete.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~40 | Brand.dev, Coresignal, Keywords Everywhere, Exa, Firecrawl, Shofo |
| Content Research | https://content.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~40 | Perplexity, Tavily, Semantic Scholar, FLUX, Ideogram, Recraft |
| Web Scraping | https://scraping.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~35 | Firecrawl, Bright Data, Jina, Olostep, ScrapeGraph, Notte |
| Developer Tools | https://devtools.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~30 | Context7, Code Runner, Python Execute, NPM Sentinel, PlantUML |
| Finance | https://finance.mcp.xpay.sh/mcp?key=YOUR_API_KEY | 253 | Financial Modeling Prep, Alpha Vantage, AkShare, Polymarket |
| Media Studio | https://media.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~25 | FLUX, Ideogram, Recraft, Stability AI, MiniMax, Kokoro |
| Social Media | https://social.mcp.xpay.sh/mcp?key=YOUR_API_KEY | 96 | ScapeCreators, Shofo, YouTube |
| Academic Research | https://research.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~30 | Semantic Scholar, Google Scholar, PubMed, arXiv |
| Marketing | https://marketing.mcp.xpay.sh/mcp?key=YOUR_API_KEY | ~30 | Keywords Everywhere, Brand.dev, Exa, Tavily, Ideogram |
How It Works
- Get a key — Sign up at app.xpay.sh and add USDC credits
- Connect — Add the endpoint URL (with your key) to any MCP client
- Call tools — Your AI assistant discovers and calls tools naturally
- Auto-deduct — Each call costs $0.01 USDC, deducted from your wallet balance
No individual provider API keys. No separate accounts. One key for 30+ providers.
Requirements
- API key from app.xpay.sh
- USDC credits in your xpay wallet (add via Coinbase)
- MCP client — Claude Desktop, Cursor, Windsurf, Claude Code CLI, Cline, etc.
How x402 Works
x402 is an open protocol for machine-to-machine payments using HTTP 402 Payment Required. When a tool call requires payment:
- Server responds with
402 Payment Required+ a payment invoice - Client signs a USDC payment on Base blockchain
- Server verifies payment and executes the tool
- Settlement is instant, non-custodial, and peer-to-peer
Browse Tools
- Hub: xpay.tools
- Docs: docs.xpay.sh
- Platform: xpay.sh
Related
@xpaysh/x402— x402 facilitator SDK@xpaysh/n8n-nodes-xpay— n8n community node@xpaysh/agent-kit-langchain— LangChain integration- xpay Facilitator — Open x402 facilitator service
License
MIT
Featured
Keep your Mac awake while Claude Code and 40+ AI agents run. Sleeps when they're idle.
One time payment $9 →Integrate web data into your AI product. One API to scrape website & brand data.
Get API Key Now →Agent, run crypto. Access onchain data & trade routes via 1inch.
Install now →On Capafy, your Skill runs online 24/7 as an agent product, and you get paid every time someone uses it.
Start earning →