x402basequality 0.35

Pay-per-call API suite on Base (USDC) covering messaging, AI, finance, and utilities at $0.02/request.

Price
0.02 USDC / call
Protocol
x402
Verified
no

What it does

lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. Every endpoint is priced at $0.02 per request, settled in USDC on the Base network. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an x402 payment header to each request.

The specific endpoint at `/api/v1/messages/160` is listed as "Premium API Access." Its x402 challenge advertises a maximum amount of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts HTTP POST and returns `application/json`. The payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a timeout of 300 seconds.

The broader platform advertises additional endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point. Documentation beyond the landing page is sparse; the /api, /pricing, and /README pages all resolve to a "Connect wallet" prompt with no further detail. Without OpenAPI specs or example request/response schemas, the exact input parameters and response formats for this endpoint remain unclear.

Capabilities

x402-paymentusdc-basepay-per-callmessaging-apijson-responseno-api-keyno-rate-limit

Use cases

  • Sending or retrieving messages via a pay-per-call model without API key management
  • Integrating low-cost, crypto-settled API calls into agent workflows
  • Accessing a variety of utility, AI, and finance endpoints from a single provider

Fit

Best for

  • Developers who want keyless, per-request billing via x402
  • AI agents that can autonomously pay for API calls with USDC on Base
  • Projects needing low-friction access to multiple endpoint categories at uniform pricing

Not for

  • Users who need detailed API documentation and typed schemas before integrating
  • High-volume consumers who need bulk pricing or subscription discounts
  • Teams that cannot settle payments in USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/messages/160 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-header>" \
  -d '{}'

Endpoint

Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no documented request/response schema, no examples, and the /api, /pricing, and /README pages are all empty beyond a wallet-connect prompt. The purpose of the specific /messages/160 endpoint is opaque.

Warnings

  • No OpenAPI or schema documentation available — request and response formats are unknown.
  • The /api, /pricing, and /README pages contain no useful content beyond 'Connect wallet'.
  • The exact purpose and parameters of /api/v1/messages/160 are undocumented; 'Premium API Access' is the only description.
  • The broader catalog of endpoints (AI, finance, utilities) is advertised but none have been individually verified.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 23:01:17Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access