realx402-seller
goodsong.dev · 8 paid endpoints · listed 2026-10-27
Verify a citation: does it exist, is it retracted, and do the given title/authors/year/journal match the canonical record? Checked against Crossref (retraction data included) with OpenAlex as a fallback when no DOI is given.
livelast check 5 days ago
100%valid x402 answers, 72 h
$0.025USDC received on Base, 7 days
3distinct payers, 7 days
54.1score (0-100)
Paid endpoints
| Method | Endpoint | Price | Networks |
|---|---|---|---|
| POST | goodsong.dev/verify/citation Verify a citation: does it exist, is it retracted, and do the given title/authors/year/journal match the canonical record? Checked against Crossref (retraction | $0.005 | Base |
| POST | goodsong.dev/verify/drug Verify an FDA drug record: given a claim_type (approval, ndc, or recall) and its identifier, does that record actually exist, and does the given name match the | $0.005 | Base |
| POST | goodsong.dev/verify/filing Verify an SEC filing: given a filer's CIK and a claimed accession number, does that filing actually exist, and does its form type/filing date match what's claim | $0.005 | Base |
| POST | goodsong.dev/verify/package Verify a package: does it exist, is it deprecated or yanked, and does it have known vulnerabilities? Checked against the npm/PyPI/crates.io registry plus OSV.de | $0.005 | Base |
| POST | goodsong.dev/verify/repo Verify a GitHub repo: does it exist, is it archived or disabled? Catches an agent recommending or depending on a repo that's been renamed, taken down, or abando | $0.005 | Base |
| POST | goodsong.dev/verify/seller Verify an x402 seller before paying it: does it exist and respond with a well-formed 402 challenge, is its own declared input/output schema internally consisten | $0.005 | Base |
| POST | goodsong.dev/verify/url Verify a URL: does it resolve, what's the final status and redirect chain, is it archived on the Wayback Machine, and (optionally) does expected text appear on | $0.005 | Base |
| POST | goodsong.dev/verify/case Verify a legal case citation: does it exist, and does the given case name match the canonical record? Catches a fabricated case citation, including a real-looki | $0.01 | Base |
Latest checks
| When | Endpoint | HTTP | ms | Result |
|---|---|---|---|---|
| 5 days ago | goodsong.dev/verify/case | 402 | 369 | valid x402 v2 terms |
Income on Base (7 days)
| Day | Transfers | USDC | |
|---|---|---|---|
| 2026-10-30 | 1 | $0.005 | |
| 2026-10-28 | 1 | $0.005 | |
| 2026-10-27 | 3 | $0.015 |
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<a href="https://logicnodes.io/observatory/p/goodsong.dev"><img src="https://logicnodes.io/observatory/badge/goodsong.dev.svg" alt="x402 status"></a>
Claim it for free with
x402_provider_claim (sign with your payout address), and get an alert within minutes when it stops answering with x402_monitor_create ($5 for 30 days). Both work over MCP (https://logicnodes.io/mcp/v2) or POST https://logicnodes.io/v1/tools/<tool>.Income is all USDC received by the provider's payout address on Base, whatever the source. Score: 0-100: 50 x share of checks in the last 72 h that returned valid x402 payment terms + 30 x min(1, log10(1 + USDC received in 7 days) / 4) + 20 x min(1, log10(1 + distinct payers in 7 days) / 3). A provider never checked scores on income only; income is all USDC received by its payout address on Base, whatever the source. JSON: /v1/observatory/providers/goodsong.dev