x402basequality 0.35

Historical USD/CHF 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/USDCHF/history

What it does

This endpoint provides historical exchange rate data for the USD/CHF currency pair. It is part of the lowpaymentfee.com platform, which offers a broad suite of pay-per-call APIs spanning finance, analytics, AI/ML, and utilities. All endpoints use the x402 protocol for payment, settling in USDC on the Base network at $0.02 per request with no API keys, rate limits, or subscriptions required.

The specific endpoint at `/api/v1/forex/USDCHF/history` accepts POST requests and returns JSON. The x402 challenge confirms it is live, advertising a maxAmountRequired of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 "exact" scheme to the provider's wallet address.

Documentation on the site 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, and no usage examples available from the crawl. The endpoint's exact input parameters (e.g., date range, granularity) and response format are unknown and must be discovered by calling the endpoint with payment.

Capabilities

forex-historyusd-chfx402-paymentusdc-basepay-per-requesthistorical-exchange-ratesjson-api

Use cases

  • —Retrieving historical USD/CHF exchange rates for backtesting trading strategies
  • —Feeding forex history into financial models or dashboards
  • —Programmatic access to currency data without API key management
  • —Agent-driven forex data retrieval with automatic micropayment

Fit

Best for

  • —Developers needing on-demand forex history without subscriptions
  • —AI agents that can pay per call via x402/USDC on Base
  • —Low-volume or sporadic forex data consumers who want no commitments

Not for

  • —High-frequency trading requiring sub-second latency and bulk data (no documented bulk endpoint)
  • —Users who need detailed API documentation or guaranteed SLAs before integrating

Quick start

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

Endpoint

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

Quality

0.35/ 1.00

The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no examples. The request body format and response structure are entirely unknown.

Warnings

  • —No API documentation available — docs, pricing, and README pages all render only 'Connect wallet' with no content.
  • —Request parameters (date range, granularity, etc.) are undocumented and must be guessed or discovered experimentally.
  • —Response schema is unknown — no example responses are available.
  • —No OpenAPI or machine-readable spec provided.
  • —The broader lowpaymentfee.com platform lists many endpoint categories but provides no detailed docs for any of them.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 04:53:14Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-29

Agent access

JSONhttps://clawmart.sh/api/listings/c7Cw5c
Historical USD/CHF forex data via x402 micropayment on Base, $0.02 per request. — Clawmart · Clawmart