KY
Payments · x402 · early usage

Swap $0.10 of USDC on Base into sats on Bitcoin Lightning: pay this route over x402, na…

Swap $0.10 of USDC on Base into sats on Bitcoin Lightning: pay this route over x402, name a Lightning address or a BOLT11 invoice for exactly the quoted sats (or with no amount), and the desk pays the sats within seconds with the preimage as the receipt. Test…

by kychange.com · discovered, not yet claimed by its owner · updated 2026-10-13

30d calls3
30d payers2
MethodPOST
Outputjson

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

Swap $0.10 of USDC on Base into sats on Bitcoin Lightning: pay this route over x402, name a Lightning address or a BOLT11 invoice for exactly the quoted sats (or with no amount), and the desk pays the sats within seconds with the preimage as the receipt. Testnet instance: Base Sepolia USDC in, Lightning testnet3 sats out.

Tags: swap · lightning · bitcoin · run402 · bazaar

Call contract

Method
POST
Input
json
Output
json
Last paid call
2026-10-13
Input example from Bazaar metadata
{
  "destination": "[email protected]"
}
Output example
{
  "sats_out": 995,
  "state": "payout_pending",
  "status_url": "https://kychange.com/api/swaps/swp_…?claim=clm_…",
  "swap_id": "swp_…"
}

Use with an agent

  1. Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
  2. Inspect. Fetch /resources/57581.json for the price and payment options.
  3. Pay. Call GET https://kychange.com/api/sats/0.10. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
  4. Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base Sepolia, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price
see accepts
Protocol
x402 v2
Auth
No account or API key. Pay per request.
Networks
Base Sepolia
Demand
3 calls · 2 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

SchemeNetworkAssetAmountPay toTimeout
exactBase Sepolia
eip155:84532
USDC1000000x58a784f2babd646ba8f5c3c1cd43493cea9feab4300s
accepts[] (raw JSON)
[
  {
    "scheme": "exact",
    "network": "eip155:84532",
    "payTo": "0x58a784f2babd646ba8f5c3c1cd43493cea9feab4",
    "asset": "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
    "amount": "100000",
    "maxTimeoutSeconds": 300
  }
]

Schemas

Output schema (JSON Schema)
{
  "properties": {
    "example": {
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}
Example shape — generated from the schema, not a captured live response
{
  "example": {},
  "type": "string"
}

Examples

curl
curl "https://kychange.com/api/sats/0.10"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid
JavaScript
const res = await fetch("https://kychange.com/api/sats/0.10");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}
Python
import httpx
res = httpx.get("https://kychange.com/api/sats/0.10")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider
kychange.com
Endpoint
https://kychange.com/api/sats/0.10
Machine-readable
/resources/57581.json