Pay-per-request premium API access on Base via x402 — $0.02/call in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. It is one of many endpoints offered by the lowpaymentfee.com platform, which hosts a collection of pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, settled in USDC on the Base network, with no API keys, rate limits, or commitments required.
The specific endpoint `/api/v1/collections/13` is labeled "Premium API Access" but its exact functionality is not documented beyond that label. The x402 challenge confirms it is live, accepts POST requests, and charges a maximum of 20,000 base units of USDC (i.e., $0.02) per call on Base. Payment is made via the x402 exact scheme to the specified wallet address. The response MIME type is `application/json`.
The broader platform advertises endpoints for metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation. However, documentation beyond the landing page is essentially empty (all sub-pages just show "Connect wallet"), so the actual capabilities and request/response schemas for this and other endpoints remain unverified.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Testing x402 payment protocol integrations against a live endpoint
Fit
Best for
- —Developers exploring x402 pay-per-request patterns
- —Agents needing keyless, on-demand API access settled in USDC on Base
- —Low-volume or sporadic API consumers who prefer no subscriptions
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —High-volume consumers who would benefit from bulk pricing or rate-limited plans
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/collections/13 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Example
Request
{
"url": "https://lowpaymentfee.com/api/v1/collections/13",
"body": {},
"method": "POST",
"headers": {
"X-PAYMENT": "<x402-payment-token>",
"Content-Type": "application/json"
}
}Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no documentation, no OpenAPI schema, no example responses, and the endpoint's actual functionality ('Premium API Access' for collections/13) is completely opaque. All doc pages beyond the landing page are empty.
Warnings
- —No documentation available — all doc/pricing/README pages return only 'Connect wallet' with no content.
- —The specific functionality of /api/v1/collections/13 ('Premium API Access') is undocumented and unclear.
- —No request or response schema is provided; callers cannot know what to send or expect back.
- —The broader platform lists many endpoints but none have verified documentation or schemas.
Citations
- —Endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/collections/13
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/collections/13
- —Documentation, pricing, and README pages contain no substantive content beyond 'Connect wallet'https://lowpaymentfee.com/docs