Send your agent on an errand.
Anthropic
OpenAI
USDG
UniswapAnthropicOpenAIUSDGUniswap
What Otsukai is
An agent that buys data or API calls needs a way to pay. Today that means a card number in a prompt, or a wallet key with everything behind it. Neither one stops a loop that pays the wrong server a thousand times.
Otsukai is the account it pays from. You fund it in USDG and give the agent a key with a per-call cap, a daily limit and a list of payees. The contract refuses every other payment, whoever submits it.
The life of an errand.
01
Fund
Open an account in one transaction and deposit USDG. You can take all of it back at any time.
02
Allow
Create a key for the agent and set its daily limit, its per-call cap, its expiry and who it may pay.
03
Ask
The agent calls a paid URL. The server answers 402 with a price, a payee and the resource.
04
Sign
The agent signs that one payment with its key. It holds no ETH and sends no transaction.
05
Settle
The contract checks every rule, pays and logs a receipt. Only then does the server answer 200.
Two sides of a payment.
Agent owners
Give Claude, an OpenAI agent or a plain script a budget in USDG. It buys what you allowed, up to the limit you set, and you revoke its key in one click.
API developers
Charge agents per call over HTTP 402. Add one middleware file and the payment settles before your response leaves the server.
Security, by limits.
Your money stays yours.
The account belongs to your wallet alone. You withdraw any amount at any time, even while it is paused. There is no admin key and no upgrade path.
Keys with a ceiling.
A key pays at most its per-call cap and its daily limit, until it expires or you revoke it. A leaked key can spend what is left of today and nothing more.
Payees you chose.
Every payment goes to an address on your allow-list. A key cannot add one, and a payment to anyone else reverts.
A receipt for every payment.
Each settlement logs a Receipt event with the agent, the payee, the amount and the resource. The app lists them and exports CSV.
Nothing leaves that you did not allow.
