x402 census · chain.openverbs.com · c41836e6b663 · JSON
POST /v1/gas-estimate
unprobed
Simulate a transaction before signing: runs `eth_estimateGas` for `{ to, from?, data?, value? }` and returns the estimated gas units and estimated fee (current gas price x gas, in wei + ETH). If the node rejects the call it returns `ok:false` with the decoded `revertReason` (why it would fail) instead of erroring. Reads live on-chain state with automatic endpoint fallback.
Verdict: not verified by an unpaid GET. not probed yet. This says nothing about whether the route works when called as declared.
Facts from the catalogs
| Field | Value |
|---|---|
| URL | https://chain.openverbs.com/v1/gas-estimate |
| Method | POST |
| Price | $0.004 USDC = 4000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 |
| Network | eip155:8453 (base) |
| payTo | 0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A |
| Seller | chain.openverbs.com |
| Catalogs | cdp (row updated 2026-09-27) |
| Listed since (lower bound) | 2026-09-27 (earliest catalog timestamp; catalogs report last-update times only) |
| Last catalog update | 2026-09-27 |
| CDP quality counters | 3 calls and 1 unique payers in 30 days, last call 2026-09-27 (catalog-reported, not verified on chain) |
| Category (keyword rule) | crypto-data |
| Templated path | no |
| x402Version in catalog | 2 |
| Service name / tags | · estimate gas, gas estimate, simulate transaction, will transaction revert, revert reason |
Unpaid probe (census of )
| Field | Value |
|---|---|
| Probe | not probed in this build |
No hourly re-probe has reached this resource yet; the cron covers a rotating slice of 150 per hour.
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": {},
"bodyType": "json",
"method": "POST",
"type": "http"
}
}
Try it (unpaid: shows the 402)
curl -si -X POST 'https://chain.openverbs.com/v1/gas-estimate' -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/c41836e6b663/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"c41836e6b663"} 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 chain.openverbs.com.