Pay-per-call API pricing for AI agents
Each tool has one price per successful call, the same over HTTP and MCP. No subscription and no account: start on the free tier, then pay with x402 or prepaid credits.
Price per successful call
Prices are in USD and identical over x402 and credits. Packages show how many calls a credits purchase covers.
| Tool | Free tier | Calls for $5 | Calls for $20 | Price |
|---|---|---|---|---|
ro_companyRomanian company file by CUI: registry, VAT, address, financials. | 10 a day | 500 | 2,000 | $0.01 |
ro_tendersSearch Romanian public tenders (SEAP/SICAP) by keyword or CPV code. | 10 a day | 250 | 1,000 | $0.02 |
us_courtSearch US court dockets and opinions on CourtListener by party. | 10 a day | 250 | 1,000 | $0.02 |
us_sanctions Coming soonScreen a person or entity against OFAC sanctions lists, fuzzy matched. | 10 a day | 500 | 2,000 | $0.01 |
us_trademarkSearch US trademark applications and registrations (USPTO) by wordmark. | 10 a day | 250 | 1,000 | $0.02 |
proof_createPaid only: capture a web page as hashed, timestamped HTML and screenshot. | Not included | 20 | 80 | $0.25 |
proof_getFetch an earlier proof: hashes, artifact links, anchor status. | Always free | – | – | free |
balanceRemaining credit of an rk_ credits key. Free. | Always free | – | – | free |
Three ways to pay, none needs an account
Order of evaluation on every call: a credits key, then the free tier, then x402.
Free tier
10 calls a day per IP address, no key, on every tool except proof_create (always paid). proof_get is always free.
Credits by card
Buy $5 or $20 and get an rk_ key, no registration. Send Authorization: Bearer rk_YOUR_KEY over HTTP or MCP.
x402
USDC on Base. Without a key, the HTTP API answers 402 with payment requirements; @x402/fetch pays and retries. HTTP only.
Questions
Am I charged for a failed call?
No. Credits are deducted and x402 payments settled only on 2xx responses. Errors, not-found lookups and coming-soon tools cost nothing.
How does the free tier work?
10 calls per UTC day per IPv4 address (or IPv6 /64), with no key, on every tool except proof_create. All free calls together are capped at 5,000 a day; past either limit a keyless call gets 402.
How do I check my balance?
GET /v1/balance with Authorization: Bearer rk_… returns { balanceUsd }; over MCP, call the balance tool. It is free. The playground shows it next to your key.
Should I use x402 or credits?
x402 pays each HTTP call in USDC on Base from the agent's wallet, with nothing bought in advance. Credits are prepaid by card and work over both HTTP and MCP. Prices are the same.
Do I need an account?
No. The free tier and x402 need nothing; a card purchase returns an rk_ key with no registration.