Agents pay for answers,not attempts.

Antera sells tool calls to AI agents over xx402, paid in $USDC. Every response is checked before the money moves: it passes and it settles, or it fails and the agent keeps its money. No deposit, no escrow, no cut.

Open the app How to use it

Live call

Checking…

verifying the response…

Listed$0.0100

Kept by agent$0.0000

Checks–

Round trip–

GET /api/call/bench?mode=ok

How it works

Sign, check, then settle.

x402 already splits checking a payment from settling it. Antera puts the call and its checks in between.

1
Quote
The agent asks. The gateway answers 402 with one exact price, payable to the provider.
2
Sign
The agent signs a USDC transfer for that price. The facilitator verifies it. Nothing moves yet.
3
Check
Antera calls the tool and checks delivery, schema, hidden errors, emptiness, duplicates, freshness and price.
4
Settle, or not
Pass: paid straight to the provider. Fail: the signature is never sent and simply expires.

Agent

Antera

Tool

402 · $0.0100signed, held200 · 3 resultsprovider paid $0.0100$

Tools

Every rule, before you spend.

Price, payee, promised failure rate and checks, published for each tool at /api/tools.

Spot price

/api/call/spot x402$0.0010per call

Latest Base block

/api/call/block x402$0.0010per call

Test bench

/api/call/bench freeFreealways

List your tool →

Timeline

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Why no escrow

Never holds your money.

	Antera	Escrow markets
Before the first call	A wallet that signs	A deposit and a minimum
Where the money waits	Nowhere, it is a signature	In an escrow contract
Cut on each call	0 %	10 % or more
A failed call	Never settled	A hold released later
The same call twice	Free for ten minutes	Charged twice
A provider's penalty	100 % to the buyers	Partly to the buyers

The bond

Providers stake real money on their promise.

Each provider locks USDC in AnteraStake and names a failure rate. The rules live in the contract, not in a terms page.

400checked calls before any penalty is possible

3σmargin over the promise, computed on chain

10 %of the stake at most in any 24 hours

100 %of every penalty goes back to the buyers

7 daysbetween asking to leave and withdrawing

0functions that let the owner move the stake

Stake behind your tool →

For agents

Any x402 client, one URL.

✓No account, no key, no deposit. A wallet with USDC on Base signs each call.
✓Never a cent over the quote. A signature for any other amount is refused.
✓Retries are free. The same paid request within ten minutes is answered again at no cost.
✓Signed receipts. Every verdict is hashed and signed, and anyone can re-check it.

Quickstart

import { wrapFetchWithPayment } from "x402-fetch";
import { privateKeyToAccount } from "viem/accounts";

const pay = wrapFetchWithPayment(fetch, privateKeyToAccount(KEY));
const r = await pay("https://www.antera.sbs/api/call/spot?asset=ETH");
const { ok, result, antera } = await r.json();

// ok === false → antera.charged === "0": the signature was never settled

Sign, check, then settle.

Quote

Sign

Check

Settle, or not