Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. The specific resource `/api/v1/messages/140` is one of many endpoints offered by the provider, which hosts a broad catalog spanning data & analytics, AI & machine learning (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, settled in USDC on the Base network.
The x402 challenge confirms the endpoint is live and accepts POST requests. Payment is made via the `exact` scheme to a specified wallet address, with a max amount of 20,000 base units of USDC (i.e., $0.02 given USDC's 6 decimals). There are no API keys required, no rate limits advertised, and access is described as instant once payment is included in the request header. The timeout window is 300 seconds.
However, the specific functionality of `/api/v1/messages/140` is unclear — it does not appear in the provider's listed catalog of endpoints, and no documentation, request schema, or response schema is available for it. The crawled pages beyond the homepage returned only "Connect wallet" prompts with no additional content. Without knowing what this particular messages endpoint returns, consumers should treat this as a loosely documented pay-per-call resource.
Capabilities
Use cases
- —Programmatic access to a premium messages resource with per-call USDC payment
- —Agent-driven API consumption without pre-registration or API keys
- —Integrating pay-as-you-go endpoints into automated workflows on Base
Fit
Best for
- —Developers wanting zero-signup, pay-per-use API access
- —AI agents that can settle x402 payments in USDC on Base
- —Prototyping with low-cost per-request pricing
Not for
- —Users needing detailed documentation or guaranteed SLAs
- —High-volume use cases where per-request crypto settlement adds latency
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/140 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but the specific resource /api/v1/messages/140 has no documentation, no request/response schema, and does not appear in the provider's own catalog. Effectively a stub listing.
Warnings
- —The endpoint /api/v1/messages/140 is not listed in the provider's published API catalog — its purpose is unknown.
- —No request or response schema is available; consumers cannot know what to send or expect back.
- —All documentation pages beyond the homepage returned only 'Connect wallet' with no useful content.
- —No OpenAPI spec, no examples, and no README content were retrievable.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (USD Coin) on Base network with 300s timeouthttps://lowpaymentfee.com/api/v1/messages/140
- —Provider offers endpoints across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com