Core concepts

Five terms appear throughout these docs and always mean the same thing.

Wallet

The agent's key and its money. It signs to prove who the agent is, and it holds the USDC the agent spends. By default Open Solid custodies the wallet for you (a managed wallet), so the agent never handles a private key. Agents that already pay from their own x402 wallet can bring it instead.

Balance

The USDC the wallet can spend, held on Solana or Base. It is the only money in the system. Every price in these docs is quoted in dollars and settled in USDC. The agent never has to think in tokens: cards are denominated in dollars and payouts arrive in dollars. The chain is plumbing.

There is a second number, the account balance, which is a ledger of deposits and purchases. Paying for something moves USDC from the wallet into the account and debits it. GET /get-account-balance shows both.

Pay-per-call

How Open Solid charges. There is no plan and no subscription. The agent calls a paid endpoint, the endpoint answers 402 Payment Required with a price, the agent pays that price in USDC, and the call goes through. That handshake is the x402 protocol. With a managed wallet, agentX402Pay runs it for you, and over MCP the paid tools settle automatically.

Fees are added to the requested amount. A $100 payout with a 4.8% fee costs $104.80 and the recipient receives $100. GET /get-pricing lists every product's fee and limits with no auth.

Credentials

The setup helper stores an API key and a short-lived session at ~/.laso/credentials.json. The session's id_token is a bearer token for every endpoint that reads or acts on the agent's own account. It expires after about an hour, and the helper renews it for free.

curl -fsS https://laso.finance/get-account-balance \
  -H "Authorization: Bearer $(jq -r .id_token ~/.laso/credentials.json)"

Never put a key in a command argument, a repository, or a chat message.

Card

A card loaded from the balance and spent at a merchant. Reloadable cards stay open across many charges and are topped up from the wallet. Use them for ad platforms and subscriptions. Prepaid cards are loaded once for an exact checkout total. A payout goes the other way: USDC leaves the balance and arrives as dollars on someone's debit card or in their bank account.