x402basequality 0.40

Historical USD/SGD forex data via x402 micropayment on Base, $0.02 per request.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/forex/USDSGD/history

What it does

This endpoint provides historical exchange rate data for the USD/SGD currency pair. It is part of the lowpaymentfee.com platform, which offers a variety of pay-per-request APIs spanning finance, analytics, AI, and utilities. The endpoint is accessed via HTTP POST and is gated by the x402 payment protocol on the Base network, accepting USDC payments.

Pricing is $0.02 per request (20,000 base units of USDC with 6 decimals). There are no API keys, no rate limits, and no subscription commitments — each call is paid individually via the x402 payment header. The payment is settled on-chain to a specified wallet address using USDC on Base.

The specific response schema for the historical forex data is not documented in the crawled material. The site's docs, pricing, and API pages all appear to require a wallet connection and provide no additional detail beyond the landing page. As a result, the exact request parameters (e.g., date range, granularity) and response format must be discovered by making an authenticated call. The endpoint is confirmed live, returning a proper 402 challenge.

Capabilities

forex-historyusd-sgdx402-paymentusdc-basepay-per-requesthistorical-exchange-rates

Use cases

  • —Retrieving historical USD/SGD exchange rates for financial analysis
  • —Backtesting trading strategies involving USD and SGD
  • —Building dashboards that display forex trends over time
  • —Feeding historical FX data into pricing or invoicing systems

Fit

Best for

  • —Agents or apps needing on-demand forex history without API key management
  • —Micropayment-friendly workflows that pay per call on Base
  • —Developers who want instant access to USD/SGD data without subscriptions

Not for

  • —High-frequency trading requiring sub-second latency and streaming data
  • —Users who need free or bulk-discounted forex data
  • —Currency pairs other than USD/SGD (this endpoint is pair-specific)

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/forex/USDSGD/history \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402_payment_token>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/forex/USDSGD/history
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.40/ 1.00

The endpoint is confirmed live with a valid 402 challenge and clear pricing ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no documented request parameters, no example responses, and the docs/pricing/API pages are all behind a wallet-connect gate, yielding no useful content.

Warnings

  • —No request parameter documentation found — input format (date range, granularity, etc.) is unknown
  • —No response schema or example response available
  • —Docs, pricing, and API pages all render only a 'Connect wallet' prompt with no public documentation
  • —The endpoint description is generic ('Premium API Access') and does not describe the data returned

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 04:53:34Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-28

Agent access

JSONhttps://clawmart.sh/api/listings/yGeqsQ
Historical USD/SGD forex data via x402 micropayment on Base, $0.02 per request. — Clawmart · Clawmart