The decentralized API marketplace where AI agents pay with USDC, not API keys.

Live: x402bazaar.org | API: x402-api.onrender.com | Dashboard: x402-api.onrender.com/dashboard

x402 Bazaar is an autonomous API marketplace built on the HTTP 402 Payment Required standard. AI agents discover services, pay in USDC on Base, SKALE on Base (ultra-low gas), or Polygon, and get instant access -- no API keys, no subscriptions, no accounts. The server verifies payments on-chain and enforces anti-replay protection, making every transaction trustless and permissionless.

• HTTP 402 Protocol -- Standard-compliant payment flow. Call an endpoint, get a 402 with payment details, pay USDC, retry with tx hash, done.
• 74 Native API Wrappers -- Web search, URL scraper, Twitter/X, weather, crypto, jokes, DALL-E 3, translation, code execution, sentiment analysis, and 64+ more -- all behind micropayments.
• 70+ Registered Services -- Growing marketplace of third-party APIs monetized through x402.
• LangChain Integration -- Python package x402-langchain for agents built with LangChain/LangGraph.
• Multi-Chain -- Base (mainnet) + SKALE on Base (ultra-low gas fees ~$0.0007/tx) + Polygon (mainnet, ~$0.001/tx via MATIC).
• MCP Server -- Plug into Claude Desktop, Cursor, VS Code, or Claude Code as native AI tools.
• One-Line Setup -- npx x402-bazaar init detects your IDE and configures everything.
• Anti-Replay Protection -- Every transaction hash is stored in Supabase and can only be used once.
• Budget Control -- Per-session spending caps for AI agents (configurable MAX_BUDGET_USDC).
• Security Hardened -- Helmet headers, CORS whitelist, rate limiting (3 tiers), input sanitization, SSRF protection.
• 1543 Tests -- 14+ test suites, all passing (node:test, zero deps).
• Real-Time Monitoring -- 74 endpoints checked every 5min, Telegram alerts on transitions, public /api/status page.
• Telegram Bot -- Interactive admin bot with 6 commands (/balance, /stats, /status, /recent, /services, /help).
• Auto-Test on Registration -- New services are pinged automatically, with Telegram notification on result.
• Public Stats -- GET /api/public-stats (no auth) for frontend homepage counters.

# One-line setup for AI IDEs (Claude Desktop, Cursor, VS Code)
npx x402-bazaar init

Or run the server locally:

git clone https://github.com/Wintyx57/x402-backend.git
cd x402-backend
npm install
cp .env.example .env   # Fill in your keys
node server.js

Agent                          x402 Bazaar                     Base / SKALE / Polygon
  |                                |                                |
  |  GET /api/weather?city=Paris   |                                |
  |------------------------------->|                                |
  |  402 Payment Required          |                                |
  |  { amount: 0.02, recipient }   |                                |
  |<-------------------------------|                                |
  |                                |                                |
  |  Transfer 0.02 USDC ------------------------------------------>|
  |  tx: 0xabc123...              |                                |
  |                                |                                |
  |  GET /api/weather?city=Paris   |                                |
  |  X-Payment-TxHash: 0xabc123   |                                |
  |------------------------------->|                                |
  |                                |  verify tx on-chain ---------->|
  |                                |  mark tx used (anti-replay)    |
  |  200 OK { temperature: 15.2 } |                                |
  |<-------------------------------|                                |

The MCP server exposes x402 Bazaar as native tools for AI IDEs. Agents can discover, search, and pay for APIs directly from their conversation.

npx x402-bazaar init   # Auto-detects your IDE and installs

npm start            # Start the server
npm run mcp          # Start the MCP server
npm run seed         # Seed 75+ services into Supabase
npm run seed:wrappers # Register the 74 native wrappers
npm run demo         # Run the autonomous agent demo
npm run demo:live    # Live demo with terminal UI

• Helmet -- Security headers (HSTS, X-Content-Type, X-Frame-Options)
• CORS -- Strict origin whitelist (no wildcards in production)
• Rate Limiting -- 3 tiers: general (500/15min), paid endpoints (30/min), registration (10/hr)
• Anti-Replay -- Transaction hashes persisted in Supabase used_transactions table
• On-Chain Verification -- Validates USDC transfer logs directly via RPC
• USDC-Only -- Rejects non-USDC token transfers
• Input Sanitization -- Control character rejection, Postgres LIKE escaping, length limits
• SSRF Protection -- Blocks localhost, private IPs, IPv6 loopback, cloud metadata
• Body Limit -- 10KB max request body
• RPC Timeout -- 10s timeout on all blockchain calls

Monetize any Python function in 5 minutes with the FastAPI template:

git clone https://github.com/Wintyx57/x402-fast-monetization-template
cd x402-fast-monetization-template
pip install -r requirements.txt
cp .env.example .env  # Set your WALLET_ADDRESS
python main.py

@x402_paywall(price=0.05, description="My API", tags=["cool"])
def my_function(text: str) -> dict:
    return {"result": "something"}

Contributions are welcome. Please open an issue to discuss proposed changes before submitting a PR.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

• Website: x402bazaar.org
• Frontend: github.com/Wintyx57/x402-frontend
• LangChain: github.com/Wintyx57/x402-langchain
• CLI: npx x402-bazaar init | npm
• API Template: x402-fast-monetization-template
• Live API: x402-api.onrender.com
• Dashboard: x402-api.onrender.com/dashboard

MIT