x402 census · math.openverbs.com · d8cc6c216bc5 · JSON
POST /v1/eval
live
Evaluate a mathematical expression with optional named variables — arithmetic, comparison and logic operators plus functions like sqrt, abs, min, max, sin, cos, log, floor, round, etc. A syntax error, an undefined variable, or a non-finite result is a clean 400. The factorial operator is disabled for safety.
Verdict: live. The unpaid GET reached a valid 402 (confirmed by the re-probe of 2026-10-01).
Facts from the catalogs
| Field | Value |
|---|---|
| URL | https://math.openverbs.com/v1/eval |
| Method | POST |
| Price | $0.004 USDC = 4000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 |
| Network | eip155:8453 (base) |
| payTo | 0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A |
| Seller | math.openverbs.com |
| Catalogs | cdp (row updated 2026-09-06) |
| Listed since (lower bound) | 2026-09-06 (earliest catalog timestamp; catalogs report last-update times only) |
| Last catalog update | 2026-09-06 |
| CDP quality counters | 3 calls and 1 unique payers in 30 days, last call 2026-09-06 (catalog-reported, not verified on chain) |
| Category (keyword rule) | other/unknown |
| Templated path | no |
| x402Version in catalog | 2 |
| Service name / tags | Evaluate expression · evaluate math expression, calculator api, compute formula, expression evaluator, math with variables |
Unpaid probe (census of )
| Field | Value |
|---|---|
| Probe | not probed in this build |
Latest re-probe
| Field | Value |
|---|---|
| Re-probed at | 2026-10-01T02:13:18.000Z (cron) |
| Verdict now | live changed from unprobed |
| HEAD / GET | 402 / 402 |
| accepts[0] | {"scheme":"exact","network":"eip155:8453","amount":"4000","payTo":"0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","maxTimeoutSeconds":300,"extra":{"name":"USD Coin","version":"2"}} |
| Live amount equals catalog price | yes |
| Latency | 3,435 ms |
| Error | none |
On-chain facts for the payTo (public address)
| Field | Value |
|---|---|
| Distinct payers | 5 |
| Payments | 197 |
| USDC volume | $1.35 |
| Median payment | $0.01 |
| First / last payment | 2026-09-09 / 2026-09-30 |
| Sampler-shaped share of payments | 100.0% |
| Payers that are not samplers | 0 |
| Source | forensics-2026-09-30 |
| Address | 0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A |
Declared input and output (extensions.bazaar)
{
"input": {
"body": {
"expression": "example",
"precision": 1,
"variables": {}
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
}
Try it (unpaid: shows the 402)
curl -si -X POST 'https://math.openverbs.com/v1/eval' -H 'accept: application/json' -H 'content-type: application/json' --data '{}'
The catalog declares POST. A 402 answer carries the payment requirements in the JSON body and, for x402 v2, base64 in the PAYMENT-REQUIRED header. This page never sends a payment.
Paid checks (x402, USDC on Base)
GET https://bazaar.agentexchange.work/r/d8cc6c216bc5/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"d8cc6c216bc5"} places this resource at the top of the report and search pages for 30 days for $1.00, labelled. Unpaid requests answer 402 with the terms. Pricing.
Catalog references: agentic.market (CDP Bazaar front end) · this record as JSON · all resources on math.openverbs.com.