x402-gated backup/data endpoint on Base, pay-per-call with USDC at $0.02 per request.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 paywall on the Base network. The specific resource `/api/v1/backups/21` is one of many endpoints offered by the provider, which hosts a broad catalog spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per request in USDC.
The x402 challenge confirms the endpoint is live and accepts payment via the "exact" scheme on Base, settling in USDC (contract 0x8335…2913) to the provider's address. The maximum amount required is 20,000 base units of USDC (6 decimals), which equals $0.02. The endpoint accepts HTTP POST requests and returns application/json. No API keys or rate limits are advertised; access is granted per-payment.
Documentation is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema, and no description of what the `/api/v1/backups/21` resource actually returns. The name "Premium API Access" and the path segment "backups/21" suggest it may return some form of backup data (possibly a specific record with ID 21), but this is speculative. Without documentation or example responses, agents should treat this endpoint as experimental.
Capabilities
Use cases
- —Retrieving backup data records via a single micropayment
- —Agent-driven data access without API keys or subscriptions
- —Programmatic pay-per-use data retrieval on Base
Fit
Best for
- —Agents needing keyless, pay-per-call data access on Base
- —Developers experimenting with x402 payment flows
- —Use cases requiring no subscription or rate-limit constraints
Not for
- —Production workloads requiring documented request/response schemas
- —Users who need free or subscription-based access
- —Bulk data retrieval where per-request fees add up quickly
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/backups/21 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no documentation, no OpenAPI spec, no request/response schema, and no explanation of what '/api/v1/backups/21' actually returns. The docs pages are empty beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet'
- —No OpenAPI or request/response schema provided; the actual data returned by /api/v1/backups/21 is unknown
- —The purpose of the 'backups/21' resource is unclear and may be a demo or placeholder endpoint
- —No examples of successful responses are available
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/backups/21
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/backups/21