@b402ai/solana

Private DeFi on Solana. Shielded balances + composable adapters + agent-callable surface.

npm install @b402ai/solana

What it does

• Shield SPL tokens into a private balance
• Unshield to any public address
• Private swap through registered adapters (Jupiter on mainnet, mock on devnet)
• Private lend USDC into Kamino V2 from a shielded note (per-user obligation, mainnet)
• Private redeem a kUSDC voucher back into a shielded USDC note (mainnet)
• Read your private balance / per-deposit holdings without leaking ZK plumbing
• Watch for new private deposits via cursor-based polling
• Quote swaps via Jupiter Lite API before executing

Quick start

Three-line private swap on mainnet:

import { B402Solana } from '@b402ai/solana';
import { Keypair, PublicKey } from '@solana/web3.js';

const b402 = new B402Solana({ cluster: 'mainnet', rpcUrl, keypair });
await b402.ready();

const USDC = new PublicKey('EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v');
const SOL  = new PublicKey('So11111111111111111111111111111111111111112');

// Move public USDC into the shielded pool (user signs, one-time).
await b402.shield({ mint: USDC, amount: 1_000_000n });

// Private swap. Hosted relayer signs + pays gas; user wallet stays off-chain.
const { signature, outAmount } = await b402.swap({
  inMint: USDC, outMint: SOL, amount: 1_000_000n,
});

Full walkthrough: docs/getting-started.md. Runnable example: examples/quickstart-private-swap.ts.

Lend privately on Kamino

b402.lend() auto-discovers the deepest Kamino reserve for the mint across all 182 LendingMarkets — no static reserve list. Pass market to pin a specific one.

const lend = await b402.lend({ mint: USDC, amount: 1_000_000n });
const redeem = await b402.redeem({ mint: USDC });

Withdraw to a different recipient

// The SOL note from `swap` can land at ANY public address — breaking
// the on-chain edge between depositor and recipient.
await b402.unshield({ to: someOtherWallet, mint: SOL });

For a working scaffold:

npx @b402ai/create-agent my-agent

Agent loop

let cursor: string | undefined;
while (running) {
  const r = await b402.watchIncoming({ cursor });
  cursor = r.cursor;
  for (const d of r.incoming) console.log('new deposit:', d.amount, d.mint);
  await sleep(2_000);
}

MCP

Same surface is exposed as agent-callable MCP tools via @b402ai/solana-mcp — works with Claude Code, Cursor and any MCP runtime.

License

Apache-2.0. See LICENSE.