x402 price index · endpoint
POST https://code402.dev/v1/tools/isbn-check/call · tool isbn-check · source self · id 1f870b99b6ad0357
- current quote
- 0.000999 USDC declared observed 2026-09-12T06:03:47.000Z
- percentile
- P55 of 197 indexed USDC quotes (share quoting at or below this one; P0 = cheapest)
- inflation flag
- no (latest quote ≤ 1.5× the 30-day median)
- 7-day
- 0.000999 USDC / 0.000999 USDC / 0.000999 USDC min / median / max · 14 obs · change 0.0%
- 30-day
- 0.000999 USDC / 0.000999 USDC / 0.000999 USDC min / median / max · 35 obs · change 0.0%
- first / last seen
- 2026-09-03T13:18:52.000Z / 2026-09-12T06:03:47.000Z
Embed the badge
The badge is served from this index with a 1-hour cache and reads "unknown" whenever there is no data. It links back here so anyone can see the history behind the number.
[](https://index.code402.dev/e/1f870b99b6ad0357)
<a href="https://index.code402.dev/e/1f870b99b6ad0357"><img src="https://index.code402.dev/badge/1f870b99b6ad0357.svg" alt="x402 quoted price for https://code402.dev/v1/tools/isbn-check/call"></a>
Verify a receipt
Paste the XDR-1 receipt JSON a paid call returned (the X-Receipt header, base64-decoded, or the receipt object inside it). The signer is recovered offline and compared with the signer https://code402.dev publishes in /.well-known/x402.json. Nothing is sent anywhere else.
Price history (last 35 observations, 30 days)
| observed | quoted | asset | chain | pay to | kind |
|---|---|---|---|---|---|
| 2026-09-12T06:03:47.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-12T00:03:00.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-11T18:02:50.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-11T12:04:12.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-11T06:03:42.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-11T00:03:24.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-10T18:02:43.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-10T12:02:43.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-10T06:02:54.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-10T00:03:43.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-09T18:03:14.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-09T12:03:14.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-09T06:02:59.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-09T00:03:11.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-08T18:03:10.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-08T12:03:00.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-08T06:03:00.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-08T00:02:48.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-07T18:02:48.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-06T12:02:58.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-06T06:03:42.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-06T00:03:19.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-05T18:03:20.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-05T12:02:55.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-05T06:02:23.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-05T00:02:23.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-04T18:02:23.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-04T12:02:24.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-04T06:02:24.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-04T00:02:23.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-03T18:02:25.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-03T14:21:33.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-03T14:10:20.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-03T14:02:20.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
| 2026-09-03T13:55:07.000Z | 0.000999 USDC | 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 | 8453 | 0xc59c85e661d34084a7769f955d17fd38254a6235 | declared |
Raw JSON: /v1/history · /v1/price