US college web census ยท fetched 2026-09-30
Pricing
Everything the census measured is free. The paid routes below are paid per call in USDC on Base with the x402 protocol; no account, no key, no subscription.
Free
| Route | What | Price |
|---|---|---|
GET https://colleges.agentexchange.work/college/<domain>.json | One census record with readable fields, CORS open | free |
GET https://colleges.agentexchange.work/college/<domain> | The same record as a page, with badge and feed | free |
GET https://colleges.agentexchange.work/datasets | CSV, NDJSON and JSON dumps (CC BY 4.0) | free |
GET https://colleges.agentexchange.work/changes.xml, /college/<domain>.xml | Atom feeds of live re-check changes | free |
GET https://colleges.agentexchange.work/trending.json, /live.json, /findings.json | Crawler demand, re-check totals, aggregates | free |
GET https://colleges.agentexchange.work/leads, /leads/<list>.top.json, /leads/<list>.xml | Gap list pages, the first 50 rows of each list with counts by state (CORS), and the feed of colleges entering or leaving a list | free |
Paid (x402)
| Route | What | Price |
|---|---|---|
POST https://colleges.agentexchange.work/listings | List a site or agent on this host's directory page for 30 days (renew by paying again) | 1.00 USDC |
GET https://colleges.agentexchange.work/college/<domain>/live.json | Live re-check of one college right now, diffed against the census record | 0.01 USDC |
GET https://colleges.agentexchange.work/leads/<list>.csv, .json | One full gap list (8 lists of 14 to 4,617 rows, 19 columns): the colleges whose census record lacks one control | 1.00 USDC |
GET https://colleges.agentexchange.work/leads/<list>/state/<code>.csv | One state of a gap list as CSV | 0.25 USDC |
POST https://colleges.agentexchange.work/watch | Change webhook for 30 days: the 6-hourly re-checks POST what changed (one gap list, one domain, or everything) to your https URL (terms) | 1.00 USDC |
How payment works
Send the request; the answer is 402 Payment Required with an accepts list (scheme exact, network Base, asset USDC, payTo 0xc91cE6291eDC0713ec753BAFBA002506ffb2b95c). Sign the EIP-3009 authorization for that amount, resend the same request with the X-PAYMENT header, and the facilitator (facilitator.payai.network) verifies and settles it on chain before the response is returned. Prices in /.well-known/x402 are identical to the challenges. Settlement is final; there are no accounts to refund. Rate limits and terms are on the terms page.