x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402 protocol API marketplace that gates a variety of endpoints behind per-request USDC micropayments on the Base network. The specific endpoint at `/api/v1/stripe/charges/138` is listed as "Premium API Access" and costs $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is made via the x402 exact scheme — no API keys, no rate limits, and no subscriptions required.
The broader platform advertises four categories of APIs: Data & Analytics (metrics, reports, data export, insights), 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 listed at the same $0.02/request price point and settle in USDC on Base to address 0x1A2B...85F3.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl. The specific functionality behind the `/api/v1/stripe/charges/138` path is unclear; the name "Premium API Access" and the path segment "stripe/charges" suggest it may relate to Stripe charge data, but this is speculative. The endpoint is confirmed live via a valid 402 challenge.
Capabilities
Use cases
- —Agents needing on-demand API access without pre-registration or API keys
- —Micropayment-gated data retrieval for analytics or finance workflows
- —AI inference tasks (sentiment, summarization, classification) paid per call
- —Utility operations like geocoding or data conversion with no subscription
Fit
Best for
- —AI agents that can settle x402 payments in USDC on Base
- —Developers wanting zero-commitment, pay-as-you-go API access
- —Prototyping workflows that need diverse API categories without signup
Not for
- —High-volume production workloads where $0.02/request adds up quickly
- —Users who need detailed API documentation or guaranteed SLAs
- —Anyone unable to transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/charges/138 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge and clear pricing ($0.02 USDC on Base). However, documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, no examples, and the actual functionality of this specific endpoint is unclear.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all return only 'Connect wallet' with no usable content.
- —No OpenAPI or schema documentation available for any endpoint.
- —The specific purpose of /api/v1/stripe/charges/138 ('Premium API Access') is unclear — the path suggests Stripe charge data but this is unconfirmed.
- —No request body schema or response schema is documented anywhere.
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 USDC base units (=$0.02) on Base networkhttps://lowpaymentfee.com/api/v1/stripe/charges/138
- —The platform lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories all at $0.02/requesthttps://lowpaymentfee.com
- —Pricing is $0.02/request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/stripe/charges/138