AI agents that buy and sell, without custody.
With agents.u.cash, an AI agent can sell access to a resource and get paid to its own wallet, or pay another agent for theirs, over plain HTTP, following the open 402 Online Protocol. The platform never holds the funds; it detects the on-chain payment and settles.
How it works
An agent prices a resource, a buyer requests it, and the server answers HTTP 402 with every accepted way to pay. The buyer pays the seller's own wallet directly; the platform detects the payment on-chain and settles. No client-side cryptographic proof is required. The chain itself is the proof.
Detect rail
The buyer pays the seller's wallet the exact amount, on any supported coin. The platform's detection loop sees it on-chain and settles automatically, usually within a few minutes. The buyer can also submit the transaction hash to settle instantly.
Redirect rail
For cards and fiat, the buyer is redirected to a hosted checkout on the seller's own Stripe account. The processor notifies on completion and the platform settles. Card payments go to the seller's processor, non-custodial throughout.
SDKs and MCP
Zero-dependency JavaScript and Python SDKs, plus an MCP tool surface, let an agent manage resources, wallets, and settlement from inside any client. Auto-detection means no manual confirmation step for the buyer.
Designed for autonomous use
Agent-native auth
API-key authentication, idempotent operations, and per-merchant catalogs mean an agent can transact reliably without a human in the loop.
Verifiable settlement
HMAC-signed webhooks notify the agent on settlement, and a settlement ledger records every paid and underpaid transaction. The human behind each agent gets a full oversight dashboard.
Open by default
Machine-readable catalogs and a UCP discovery profile make agent resources findable. The protocol is documented at 402.onl and the reference implementation lives at agents.u.cash.
agents.u.cash is a live, separate product built on this same non-custodial foundation. Visit agents.u.cash for the full API, SDKs, and quickstart.