X402 Bazaar MCP Server

x402-bazaar-mcp

An MCP (Model Context Protocol) server that exposes every paid API in the x402 Bazaar catalog as a callable tool for AI agents (Claude Desktop, Cursor, custom agents, etc.).

Each tool call is backed by an x402 micro-payment in USDC on Base — no API keys, no subscriptions, no sign-up. The agent pays only for what it uses, typically fractions of a cent per call.

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How it works

1. On startup the server fetches the live catalog from https://402.com.tr/api/catalog and auto-registers one MCP tool per service.
2. When an AI agent calls a tool the server builds the request URL, hits the endpoint, and transparently handles the x402 payment flow: HTTP 402 → pay USDC on Base → retry → return response.
3. The agent wallet only needs USDC on Base. Gas is paid by the x402 facilitator — it is gasless for the payer.

First few calls per day per service may be served on the free tier at no cost; subsequent calls trigger micro-payments automatically.

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Requirements

• Node.js ≥ 20
• A Base wallet private key whose address holds USDC on Base mainnet

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Installation & running

# Install dependencies
npm install

# Run (set your private key in the environment)
AGENT_PRIVATE_KEY=0xYOUR_PRIVATE_KEY npx x402-bazaar-mcp

Or with npm start after cloning:

AGENT_PRIVATE_KEY=0xYOUR_PRIVATE_KEY npm start

Environment variables

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Claude Desktop configuration

Add the following to your claude_desktop_config.json (usually ~/Library/Application Support/Claude/claude_desktop_config.json on macOS or %APPDATA%\Claude\claude_desktop_config.json on Windows):

{
  "mcpServers": {
    "x402-bazaar": {
      "command": "npx",
      "args": ["-y", "x402-bazaar-mcp"],
      "env": {
        "AGENT_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY"
      }
    }
  }
}

After saving, restart Claude Desktop. You should see the Bazaar tools appear in the tool list (hammer icon).

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Cursor / other MCP clients

Any MCP-compatible client that supports stdio servers works the same way — just point it at npx x402-bazaar-mcp with AGENT_PRIVATE_KEY in the environment.

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Why agents use this

Agents need fresh on-chain data and AI utilities but don't want to manage RPC endpoints, scrapers, security heuristics, or per-provider API keys. One MCP server plus a funded wallet gives them everything — contract safety checks, live DEX prices, gas estimates, transaction decoding, and Claude-powered text utilities — all pay-per-use, with no subscriptions or sign-up required.

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What your agent can do (tools)

Tools are loaded live from the catalog, so the list stays current. At the time of writing it includes:

Example

Once installed, just ask your agent naturally — it picks the right tool and pays per call:

"Is 0x… a safe token to buy on Base? Check the risk and current price."

The agent calls token_risk and token_price, each settling a tiny USDC payment from your wallet, and answers with the on-chain data.

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Sample outputs

token_risk — low-risk token

{
  "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "isContract": true,
  "token": {
    "name": "USD Coin",
    "symbol": "USDC",
    "decimals": 6,
    "totalSupply": "4800000000000000"
  },
  "ownership": {
    "owner": "0x0000000000000000000000000000000000000000",
    "renounced": true
  },
  "upgradeableProxy": false,
  "security": {
    "isHoneypot": false,
    "buyTaxPct": 0,
    "sellTaxPct": 0,
    "isOpenSource": true,
    "isMintable": false,
    "transferPausable": false,
    "canTakeBackOwnership": false,
    "hiddenOwner": false,
    "holderCount": 182430,
    "topHolderPct": 12.47,
    "top10HolderPct": 41.22,
    "lockedLpPct": 100,
    "creatorPct": 0,
    "isInDex": true,
    "isAntiWhale": false,
    "antiWhaleModifiable": false,
    "tradingCooldown": false,
    "slippageModifiable": false,
    "isTrueToken": true,
    "isAirdropScam": false,
    "creatorAddress": "0x6B175474E89094C44Da98b954EedeAC495271d0F",
    "creatorBalance": "0"
  },
  "riskScore": 0,
  "riskLevel": "low",
  "flags": [],
  "sources": ["base-rpc", "goplus"],
  "coverage": "RPC base + GoPlus security (honeypot, taxes, holders, holder concentration, LP lock, creator holdings, source, ownership controls).",
  "checkedAt": "2026-06-23T09:14:02.381Z"
}

token_price — DEX price and liquidity

{
  "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "priceUsd": "0.9998",
  "priceChange24h": -0.03,
  "liquidityUsd": 4721850.44,
  "volume24h": 18340210.77,
  "dexId": "uniswap",
  "pairAddress": "0x88A43bbDF9D098eEC7bCEda4e2494615dfD9bB9C",
  "baseToken": {
    "name": "USD Coin",
    "symbol": "USDC"
  },
  "checkedAt": "2026-06-23T09:14:03.105Z"
}

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Discovering available services

• Human-readable catalog & docs: https://402.com.tr/agents
• Machine-readable catalog (used by this server): https://402.com.tr/api/catalog
• x402 well-known: https://402.com.tr/.well-known/x402

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Security note

Your private key is only used locally inside this process to sign payment authorizations. It is never sent to the Bazaar server or any third party. Use a dedicated spending wallet (not your main wallet) and keep only a small USDC balance on it.

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License

MIT