SNAP — Shield Network Agent Payments

Private agent-to-agent payments on Solana using zero-knowledge proofs.

Status: SNAP is in a tightly capped limited-release phase. Do not treat the current codebase or docs as audited deployment guidance.

What SNAP Does

SNAP lets AI agents pay each other without on-chain observers learning who paid whom. Deposits enter a shielded pool under a cryptographic commitment. Withdrawals leave the pool with a Groth16 proof that shows the recipient is entitled to the funds without revealing which deposit is being claimed.

How It Works

1. Agent A deposits SOL plus a commitment into the pool.
2. Agent A sends a secret note to Agent B through a private channel.
3. Agent B reconstructs the Merkle path and generates a Groth16 proof.
4. Agent B withdraws SOL with withdraw_zk or withdraw_zk_relayed.
5. Observers can see the pool activity, but they cannot link the withdrawal to a specific deposit.

Quick Start

Install the SDK and its peer dependencies:

npm install snap-solana-sdk @solana/web3.js @coral-xyz/anchor

Minimal private payment:

import { Connection, Keypair, PublicKey, clusterApiUrl } from "@solana/web3.js";
import { SNAPClient } from "snap-solana-sdk";

async function main() {
  const connection = new Connection("https://your-rpc-url.com", "confirmed");
  const sender = Keypair.generate();
  const recipient = Keypair.generate();
  const pool = new PublicKey("B8SyffZKt8LABKogWjH9rZcjY5PV2hyYRCbTxxbcrpFf");

  const snapA = new SNAPClient(connection, sender);
  const snapB = new SNAPClient(connection, recipient);

  const note = await snapA.deposit(pool, 0.1);
  const serialized = SNAPClient.serializeNote(note);
  await snapB.withdraw(pool, SNAPClient.deserializeNote(serialized), recipient);
}

void main();

If you want a runnable walkthrough from this repo, use:

npx tsx examples/basic-payment.ts
npx tsx examples/agent-to-agent.ts
npx tsx examples/relayed-withdrawal.ts

Architecture

Component	Description
Solana Program	Anchor program with deposit, withdraw_zk, and withdraw_zk_relayed
ZK Circuit	circom Groth16 circuit using Poseidon and a depth-10 Merkle tree
SDK	snap-solana-sdk for note handling, proof generation, and client API
Agent Kit Plugin	Solana Agent Kit v2 plugin with snap_create_pool, snap_deposit, snap_withdraw, and snap_withdraw_private
Relayer	Express service for gas-abstracted private withdrawals

Mainnet

This is a limited release. The protocol has not been audited by a third party. Pool denominations are intentionally small. Do not deposit more than you can afford to lose.

Field	Value
Program ID	9uePoqdgaXpqFLQM2ED1GGQrwSEiqe3r6tW1AfsnrrbS
Pool — 0.1 SOL	B8SyffZKt8LABKogWjH9rZcjY5PV2hyYRCbTxxbcrpFf
Pool — 1 USDC	5LeuHrPBgHNhgbCy996MEjcsBk5gNHhVj6AiuuCHZ8od
Pool — 10 USDC	ECuHf8kgiWfmL3Q6id4WGBQWvuukhzqvF5vsxuPAKZBv
Network	Solana mainnet-beta
Protocol fee	0.25%

Project Structure

├── programs/           # Solana program (Rust/Anchor)
├── circuits/           # circom ZK circuit
├── sdk-package/        # snap-solana-sdk npm package
├── agent-kit-tool/     # Solana Agent Kit plugin
├── relayer/            # Express relay service
├── agents/             # Demo agent scripts
├── examples/           # Minimal end-to-end examples
├── scripts/            # Deployment and quickstart scripts
├── docs/               # Troubleshooting, circuit, and compliance docs
└── tests/              # Integration tests

Development

# Build the Solana program
anchor build

# Run validator-backed tests
PATH="$HOME/.local/share/solana/install/active_release/bin:$PATH" anchor test --skip-build

# Build and test the SDK package
cd sdk-package && npm install && npm run build && npm test

Security

This is a limited release intended for review and testing. It is unaudited; known risks, protocol limits, and hardening work are documented in FINDINGS.md, docs/CIRCUIT_SPEC.md, docs/COMPLIANCE.md, and docs/GOVERNANCE.md.

License

MIT