@b402ai/mcp

Private DeFi MCP server for AI agents. Every DeFi primitive on Base — privately.

12 tools. ZK proofs. Gasless. No wallet trace on-chain.

Install

claude mcp add b402 --scope user -e WORKER_PRIVATE_KEY=0x... -- npx -y @b402ai/mcp@latest

Or for Cursor / other MCP clients, add to your config:

{
  "mcpServers": {
    "b402": {
      "command": "npx",
      "args": ["-y", "@b402ai/mcp@latest"],
      "env": {
        "WORKER_PRIVATE_KEY": "0x..."
      }
    }
  }
}

Tools

Privacy Pool

| Tool | Description | |------|-------------| | shield_usdc | Move USDC into Railgun privacy pool (ZK encrypted) | | check_pool_balance | Check shielded balances, wallet, and positions | | private_swap | Swap tokens inside the pool (ZK proof, no trace) | | lend_privately | Deposit to Morpho vault from pool (3-4% APY) | | redeem_privately | Withdraw from vault back to pool | | run_strategy | Autonomous: swap + lend + reserve, all private |

Credit Payments (optional, requires SEQUENCER_URL)

| Tool | Description | |------|-------------| | check_balance | Check agent credit balance | | topup_credits | Add USDC credits | | open_session | Open credit session with spending cap | | pay_privately | BLS-signed API payments (batch N calls) | | close_session | Close session, refund unspent | | settle_batch | On-chain settlement + BLS proof verification |

Example

> check my private pool balance

Privacy Pool:
  USDC: 60.32
  WETH: 0.001

> run a private yield strategy with $10 USDC

Strategy deployed:
  1. Private swap: 2 USDC → 0.001 WETH
  2. Private lend: 4 USDC → Steakhouse vault (3% APY)
  3. Reserve: 4 USDC stays shielded

  3 operations. 0 wallet trace. All gasless.

How it works

Every operation goes through Railgun's privacy pool using zero-knowledge proofs. On-chain, only a relay contract appears — no wallet is ever linked to the transactions.

• Gasless — no ETH needed, gas is sponsored
• Anonymous — fresh wallet derived from your key, no on-chain identity
• ZK-proven — client-side Groth16 proofs for every private operation
• Base mainnet — real DeFi (Morpho, Aerodrome, 0x), real yield

Environment

| Variable | Required | Description | |----------|----------|-------------| | WORKER_PRIVATE_KEY | Yes | Base wallet private key | | BASE_RPC_URL | No | Base RPC (default: public) | | SEQUENCER_URL | No | Credit sequencer URL (enables payment tools) |

Links

• SDK: @b402ai/sdk
• Docs: b402.ai
• GitHub: b402ai/b402-sdk