Agent wallet (x402, testnet)

The x402 rung pays machine-to-machine with testnet USDC on Base Sepolia. The custody model is deliberate and simple: you own the keys. The wallet is generated on your machine, stored encrypted at rest (scrypt and AES-256-GCM, file mode 600), and never uploaded. The Tab Authority sees addresses and receipts, nothing else; there is no server-side wallet code at all.

1. Create the wallet

pnpm wallet:init

Pick a passphrase (at least 8 characters, remember it; it is needed to sign payments). The command prints your address. Non-interactive environments can set MOLT_WALLET_PASSPHRASE; the file lives at ~/.molt/wallet.json or wherever MOLT_WALLET_PATH points.

2. Fund it (free, ~2 minutes)

Open faucet.circle.com, choose Base Sepolia as the network, paste your address, request USDC. This is Circle's official testnet faucet; the tokens are play money. You do not need any ETH: x402 payments are signed transfer authorizations (EIP-3009) and the facilitator carries the gas.

3. Verify

pnpm wallet:balance

Faucet transfers usually land within a minute.

Custody model, stated plainly

• Keys are generated and stored only on the operator's machine.
• The Tab Authority never sees, stores, or transports key material (guardrail G4).
• Testnet only in v1: the chain allowlist is hard-coded to Base Sepolia in test mode.
• Losing the passphrase loses the wallet. It holds testnet tokens, so the correct recovery is: create a new one.