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.

Works with zero config. Run it with no wallet and no token and it uses the free tier (one free call/day per service, then a preview) — so an agent can try every tool instantly. Unlock unlimited paid calls with either a prepaid credit token (buy once, no wallet, no signing) or a wallet key.

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 picks a payment mode (below), hits the endpoint, and returns the response.
3. In wallet mode the x402 flow is transparent: HTTP 402 → pay USDC on Base → retry → return response, gasless for the payer (the facilitator pays gas).

Three payment modes (precedence order)

| Mode | Set | What happens | Wallet? Signing? | |---|---|---|---| | Credits ⭐ | X402_CREDIT_TOKEN | Sent as x-credit-token; each call debits your prepaid balance | No / No | | Wallet | AGENT_PRIVATE_KEY | Signs an x402 USDC payment locally per call | Yes / Yes | | Free | (nothing) | Free tier: 1 full call/day/service, then a preview | No / No |

Credits are the easiest paid mode: call the buy_credits tool once (or buy at 402.com.tr) to get a ck_… token, set it as X402_CREDIT_TOKEN, and every call just draws down the balance — no private key ever touches the config.

Requirements

• Node.js ≥ 20
• (optional, for paid calls) a prepaid credit token or a Base wallet private key whose address holds USDC on Base mainnet

Installation & running

npm install

# Zero-config — free tier, try every tool instantly:
npx x402-bazaar-mcp

# Paid via prepaid credits (recommended — no wallet, no signing):
X402_CREDIT_TOKEN=ck_your_token npx x402-bazaar-mcp

# Paid via wallet:
AGENT_PRIVATE_KEY=0xYOUR_PRIVATE_KEY npx x402-bazaar-mcp

Environment variables

| Variable | Required | Default | Description | |---|---|---|---| | X402_CREDIT_TOKEN | no | — | Prepaid credit token (ck_…) from buy-credits. Sent as x-credit-token; debits your balance per call. No wallet needed. Recommended paid mode. | | AGENT_PRIVATE_KEY | no | — | Hex private key for a Base wallet holding USDC. 0x prefix optional. Used only if no credit token is set. | | X402_BAZAAR_CATALOG | no | https://402.com.tr/api/catalog | Override the catalog URL (useful for local dev). |

With none of the above set, the server runs on the free tier.

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": {
        "X402_CREDIT_TOKEN": "ck_your_token"
      }
    }
  }
}

Omit the env block entirely to run on the free tier (great for a first try), or use "AGENT_PRIVATE_KEY": "0x…" instead of the credit token to pay from a wallet.

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

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.

Use with Coinbase AgentKit, Agentic Wallet & Claude Code

Because this is a standard MCP stdio server, any MCP-capable agent runtime can load and pay for the Bazaar's tools — including Coinbase's own agent stack, with no bespoke integration:

Coinbase Agentic Wallet (npx awal)

Coinbase Agentic Wallets ship native x402 support and an MCP interface. Point the wallet's MCP config at npx x402-bazaar-mcp, and the agent can call — and pay for — any Bazaar service straight from its MPC-secured wallet, gasless on Base. The x402 payment handshake is handled for you: HTTP 402 → pay USDC on Base → retry → response.

Coinbase AgentKit

AgentKit agents that support MCP servers load the Bazaar tools the same way (command: npx, args: ["-y", "x402-bazaar-mcp"], AGENT_PRIVATE_KEY in env). The agent gains on-chain safety/intel + AI tools as pay-per-call actions — token risk, honeypot/sellability checks, deployer reputation, exit liquidity, live DEX prices, gas, tx decode, and Claude-powered reports — without writing an action provider for each.

Claude Code

Add it as an MCP server in one command:

# Free tier (zero config):
claude mcp add x402-bazaar -- npx -y x402-bazaar-mcp

# Or paid via prepaid credits:
claude mcp add x402-bazaar -e X402_CREDIT_TOKEN=ck_your_token -- npx -y x402-bazaar-mcp

Then ask Claude Code to check a token, price a portfolio, or screen an address — it calls the right Bazaar tool and settles the micro-payment automatically.

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.

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:

| Tool | Price | What it does | |---|---|---| | token_risk | $0.02 | Token safety score (honeypot, taxes, ownership, holders) for any Base token | | sanctions | $0.01 | Screen an address against the OFAC sanctions list | | holders | $0.01 | Top holders, concentration (whale risk) & LP lock for a token | | token_price | $0.01 | DEX price + liquidity for a Base token | | multi_price | $0.01 | Prices for up to 10 Base tokens in one call | | address_intel | $0.01 | EOA/contract, ETH+USDC balance, activity for any address | | wallet_tokens | $0.01 | Portfolio of major Base tokens + USD value | | gas_oracle | $0.005 | Live Base gas estimates (slow/normal/fast) | | tx_decode | $0.01 | Structural decode of a Base transaction | | contract_abi | $0.01 | Is a contract verified? Get its ABI (Sourcify) | | decode_selector | $0.005 | Resolve a 4-byte selector to function signatures | | basename | $0.005 | Resolve Basenames ↔ addresses on Base | | trending_tokens / new_tokens | $0.005 | Trending & freshly listed Base tokens | | price_alert | $0.05 | Register a webhook alert when a token crosses a price | | ai_summarize / ai_extract / ai_translate | $0.02 | Claude-powered text utilities |

…plus more — the tool list is loaded live from the catalog, so it always reflects the current marketplace (70+ services, including pre_trade_gate, whale_flow, watchlist_diff, the B20 safety suite, and buy_credits).

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.

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"
}

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

Security note

Prepaid credits (recommended) need no wallet at all — the ck_… token is a bearer capability worth only its remaining balance, so a leaked token can lose at most what's left on it, never a wallet. Buy a small pack and rotate it if needed.

If you use wallet mode instead, 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.

License

MIT