Plain-HTTP twin of the Alion MCP server. Every tool is also a GET/POST endpoint. Send "Authorization: Bearer <key>" (a key from https://alion.io/developers/keys); calls are paid from the account's credits. Or pay a paid tool per call in USDC with x402 (https://x402.org), no account: call it without a key, sign one of the offers in the PAYMENT-REQUIRED header of its 402 and repeat the call with the PAYMENT-SIGNATURE header; or with MPP (https://paymentauth.org): answer a WWW-Authenticate: Payment challenge with Authorization: Payment <credential> (USDC on Base or Solana, a transfer you sign or
Data: x402-list.com (CC BY 4.0) Credit: 402 Index (MIT)
Unclaimed has 1 live API on PayAPI Market with 15 endpoints in total, in Finance: Alion: company, startup and market intelligence.
Are Unclaimed's APIs verified?
Not yet. Unclaimed's listings are live and answer an x402 payment challenge, but PayAPI Market has not paid for a call to them, so none carries a settlement-verified badge.
How do I pay for Unclaimed's APIs?
Per request, in USDC, over the x402 protocol. An agent calls the endpoint, receives HTTP 402 with the price and wallet, pays and retries. There is no API key, account or subscription, and Unclaimed keeps 100% of each payment.