FHE x402 Payment Skill
Private, encrypted payments for autonomous agents on Ethereum using Zama's Fully Homomorphic Encryption (fhEVM). All payment amounts are encrypted on-chain — only the payer and payee can see them.
Quick Start
Set a wallet and RPC, then run any command:
# Minimal setup (local dev)
export USER_PRIVATE_KEY=0x...
export RPC_URL=https://sepolia.infura.io/v3/YOUR_KEY
# Check wallet info
run info
# Wrap 10 USDC into encrypted cUSDC
run wrap --amount 10
# Send 1 encrypted cUSDC
run pay --to 0xRecipient --amount 1
# Check balance (with optional decrypt)
run balance
run balance --decrypt true
Commands
Token Operations
| Command | Description | Required Args |
|---|
| --------- | ------------- | --------------- |
wrap | Wrap USDC into encrypted cUSDC (ERC-7984) | --amount |
unwrap | Initiate unwrap of cUSDC back to USDC (step 1 of 2) | --amount |
finalize-unwrap | Complete unwrap via KMS decryption proof | --handle (recommended) or --requestId --cleartextAmount --proof (legacy) |
pay | Send encrypted cUSDC via verifier relay | --to --amount |
balance | Check USDC + cUSDC balances | Optional: --decrypt true, --of 0xAddress |
info | Display wallet, network, and contract addresses | (none) |
Escrow (Agentic Commerce Protocol — ERC-8183)
| Command | Description | Required Args |
|---|
| --------- | ------------- | --------------- |
create-job | Create an escrow job with provider + evaluator | --provider --evaluator --expiry --description Optional: --hook |
fund-job | Encrypt budget + fund a job (3-step TX) | --jobId --amount |
complete-job | Approve or reject a submitted job | --jobId --action (approve/reject) Optional: --reason |
Identity & Reputation (ERC-8004)
| Command | Description | Required Args |
|---|
| --------- | ------------- | --------------- |
register-agent | Mint an agent identity NFT | --uri |
give-feedback | Submit proof-linked reputation feedback | --agentId --score --nonce Optional: --tag1 --tag2 --endpoint --feedbackURI --feedbackHash |
Delegation (FHE Viewing Keys)
| Command | Description | Required Args |
|---|
| --------- | ------------- | --------------- |
grant-view | Grant read access to your encrypted balance | --delegate Optional: --hours --permanent --contract |
revoke-view | Revoke a delegate's view access | --delegate |
view-as | Read another agent's balance via delegation | --delegator |
Demo Orchestrators
| Command | Description | Required Args |
|---|
| --------- | ------------- | --------------- |
research-and-visualize | Chain 3 paid API calls (search + LLM + image) | --query |
review-and-rate | Buy a code review + submit feedback | --code Optional: --language --score |
Wallet Modes
Set WALLET_MODE to choose explicitly, or omit for auto-detection (DFNS > user key):
| Mode | Env Var | Best For |
|---|
| ------ | --------- | ---------- |
user | USER_PRIVATE_KEY | Local development, testing |
dfns | DFNS_WALLET_ID + DFNS_AUTH_TOKEN + DFNS_CREDENTIAL_ID + (DFNS_CREDENTIAL_PRIVATE_KEY or DFNS_PRIVATE_KEY_PATH) | Unattended MPC agents |
ledger-bridge | LEDGER_BRIDGE_URL + LEDGER_BRIDGE_TOKEN | Supervised hardware wallet |
Environment Variables
Required
| Variable | Description |
|---|
| ---------- | ------------- |
RPC_URL | Ethereum RPC endpoint (default: Sepolia public node) |
USER_PRIVATE_KEY or DFNS_WALLET_ID | At least one wallet source |
Optional
| Variable | Description |
|---|
| ---------- | ------------- |
CHAIN | mainnet or sepolia (auto-detected from RPC_URL) |
CUSDC_ADDRESS | Override cUSDC token address |
VERIFIER_ADDRESS | Override X402PaymentVerifier address |
ESCROW_ADDRESS | Override AgenticCommerceProtocol address |
IDENTITY_ADDRESS | Override AgentIdentityRegistry address |
REPUTATION_ADDRESS | Override AgentReputationRegistry address |
All contract addresses auto-fill for Sepolia when RPC_URL points to chain ID 11155111.
How It Works
- Encrypted Payments: Uses Zama's fhEVM to encrypt USDC into cUSDC (ERC-7984). All transfers are confidential — amounts are FHE-encrypted on-chain.
- x402 Protocol: Implements the HTTP 402 payment flow — servers return
402 Payment Required, the agent encrypts and pays, then retries with a payment proof header. - Escrow: The AgenticCommerceProtocol (ERC-8183) holds encrypted budgets in escrow. Jobs flow through: create → setBudget → fund → submit → complete/reject.
- Identity: Agents register as ERC-721 NFTs with EIP-712 wallet linking and on-chain metadata.
- Reputation: Proof-of-payment feedback system prevents sybil attacks on agent ratings.
Deployed Contracts (Sepolia)
| Contract | Address |
|---|
| ---------- | --------- |
| cUSDC (ERC-7984) | 0x7c5BF43B851c1dff1a4feE8dB225b87f2C223639 |
| X402PaymentVerifier | 0xD46E80E1d37116B44c7Bfd845A110FCbB93d3E9F |
| AgenticCommerceProtocol | 0xECD7a2382A5F0e3b6A7b76536e4CAE11215Cc695 |
| AgentIdentityRegistry | 0x36666464daa16442Fc1d901acfC9419f11407741 |
| AgentReputationRegistry | 0x1649d762Ee62f194D92B93510b8f10a501cE9fD5 |
Output Format
All commands return JSON strings: { "ok": true, ... } on success, { "ok": false, "error": "..." } on failure. Commands never throw — errors are returned as JSON.