x402basequality 0.35

Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/inbox/80

What it does

lowpaymentfee.com is an x402-enabled API platform that offers a broad set of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. Every endpoint costs $0.02 per request, paid 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/inbox/80` is listed as "Premium API Access" and accepts POST requests. Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, which has 6 decimals), equating to $0.02 per call. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.

The broader platform advertises 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. However, the exact functionality behind the `/api/v1/inbox/80` path is not documented beyond the generic "Premium API Access" label, so its specific input/output schema is unknown.

Capabilities

x402-paymentusdc-basepay-per-requestpost-endpointno-api-keyno-rate-limit

Use cases

  • —Programmatic access to a pay-per-call API without managing API keys or subscriptions
  • —Agent-driven workflows that need on-demand API calls settled in USDC on Base
  • —Testing x402 payment flows against a live, low-cost endpoint

Fit

Best for

  • —Developers or agents wanting zero-friction, keyless API access
  • —Micropayment experimentation on Base L2 with USDC
  • —Scenarios where per-call billing is preferred over subscriptions

Not for

  • —Users who need detailed documentation or guaranteed SLAs for production workloads
  • —Callers who cannot settle payments in USDC on the Base network
  • —Use cases requiring known, well-documented input/output schemas

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/inbox/80 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-token>" \
  -d '{}'

Example

Request

{
  "url": "https://lowpaymentfee.com/api/v1/inbox/80",
  "body": {},
  "method": "POST",
  "headers": {
    "X-PAYMENT": "<x402-payment-token>",
    "Content-Type": "application/json"
  }
}

Endpoint

URLhttps://lowpaymentfee.com/api/v1/inbox/80
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, the specific functionality of /api/v1/inbox/80 is entirely undocumented — no input schema, no output schema, no examples, and no description beyond the generic 'Premium API Access' label. The crawled pages beyond the homepage returned only 'Connect wallet' with no useful content.

Warnings

  • —The exact purpose and input/output schema of /api/v1/inbox/80 are unknown — 'Premium API Access' is not descriptive
  • —No OpenAPI spec, no detailed docs, and ancillary pages (/api, /pricing, /README) returned no useful content
  • —The platform lists many endpoints on its homepage but none have documented schemas or example responses
  • —Cannot verify what data or service this specific endpoint actually provides

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-22 00:17:38Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/Jba9bw
Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required. — Clawmart · Clawmart