USD/HKD forex exchange rate via x402 micropayment on Base network
What it does
This endpoint provides the current USD to HKD foreign exchange rate, accessible through the x402 payment protocol on the Base network. Each request costs $0.02 (20,000 base units of USDC on Base), with no API keys, rate limits, or subscriptions required — just a per-call micropayment.
The endpoint is hosted on lowpaymentfee.com, which offers a broad catalog of pay-per-request APIs spanning finance, AI/ML, data analytics, and utility services, all priced at $0.02 per call. This specific endpoint targets the USD/HKD currency pair and returns JSON. The x402 challenge confirms the endpoint is live, accepting POST requests, and settling payments in USDC (contract 0x8335…) on the Base L2 network.
Documentation beyond the landing page is sparse — the /docs, /pricing, and /README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no example request/response schema, and no description of the response payload structure. The endpoint is functional and discoverable, but consumers should expect to experiment with the request format and interpret the response without formal documentation.
Capabilities
Use cases
- —Fetching the current USD/HKD exchange rate for financial applications
- —Programmatic currency conversion in trading bots or portfolio trackers
- —Agent-driven forex lookups without API key management
- —Embedding live FX data into dashboards or reports
Fit
Best for
- —AI agents needing on-demand forex data with no signup
- —Developers wanting pay-per-use currency rate access on Base
- —Applications requiring USD/HKD spot rates without subscription commitments
Not for
- —High-frequency trading requiring sub-millisecond latency and bulk rate feeds
- —Users who need historical forex time-series data (only current rate is indicated)
- —Consumers without a Base-network USDC wallet for x402 payments
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/forex/USDHKD/rate \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_header>"Endpoint
Quality
The x402 challenge is live and confirms pricing, network, and asset details. However, there is no OpenAPI spec, no documented request/response schema, and all documentation pages beyond the landing page are empty stubs. The endpoint's actual response format must be inferred.
Warnings
- —No OpenAPI or schema documentation available — response format is unknown
- —All doc/pricing/README pages render only 'Connect wallet' with no content
- —No example request or response payloads are documented anywhere
- —The broader lowpaymentfee.com catalog lists many endpoints but none have detailed docs
Citations
- —Endpoint returns HTTP 402 with x402 challenge confirming it is livehttps://lowpaymentfee.com/api/v1/forex/USDHKD/rate
- —Price is 20,000 base units of USDC (6 decimals) = $0.02 per requesthttps://lowpaymentfee.com/api/v1/forex/USDHKD/rate
- —Payment settles in USDC on Base network to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3https://lowpaymentfee.com/api/v1/forex/USDHKD/rate
- —Site advertises $0.02/request, no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Documentation pages (/docs, /pricing, /README) contain only 'Connect wallet' with no technical contenthttps://lowpaymentfee.com/docs