x402-gated backup/data endpoint on Base, pay $0.02 per request in USDC — no API keys needed.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" resource at the path `/api/v1/backups/2025-12`. It is part of a broader platform offering multiple x402-protocol pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request, settled in USDC on the Base network.
The specific endpoint probed (`/api/v1/backups/2025-12`) returned a valid x402 challenge (HTTP 402) confirming it is live. The challenge specifies payment of up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 "exact" scheme to address 0x1A2B…85F3, with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`.
Documentation on the site is extremely thin — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema, and no explanation of what the `/api/v1/backups/2025-12` resource actually returns. The endpoint name suggests it may deliver a backup or archived dataset for December 2025, but this is speculative. Without documentation or example payloads, integrators will need to experiment after paying to discover the response format.
Capabilities
Use cases
- —Retrieving backup or archived data for December 2025 via a single paid request
- —Programmatic agent-driven data access without API key provisioning
- —Micropayment-gated data delivery settled on Base L2
Fit
Best for
- —Agents or scripts that need keyless, pay-as-you-go access to data endpoints
- —Developers experimenting with x402 protocol integrations
- —Scenarios requiring on-chain USDC micropayments for API access
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who prefer subscription-based pricing over per-call payments
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/backups/2025-12 \
-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, but there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no explanation of what the backup resource actually contains. Effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, API, and README pages all show only 'Connect wallet'
- —No request or response schema provided; payload format is unknown
- —The resource path '/api/v1/backups/2025-12' is unexplained — unclear what data it returns
- —This specific endpoint is not listed on the site's landing page among the advertised APIs
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/backups/2025-12
- —All listed APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/backups/2025-12