Historical stock data for UNP (Union Pacific) via x402 micropayment on Base, $0.02/request.
What it does
This endpoint provides historical stock price data for Union Pacific Corporation (ticker: UNP) through the x402 payment protocol. It is part of a broader suite of paid APIs hosted at lowpaymentfee.com, which spans data analytics, AI/ML inference, finance, crypto, and utility services — all priced at $0.02 per request and settled in USDC on the Base network.
The endpoint accepts POST requests and returns JSON. Payment is handled inline via the x402 protocol: callers include an X-PAYMENT header with a signed USDC payment of up to $0.02 (20,000 base units of USDC, 6 decimals). No API keys or accounts are required; access is granted per-request upon valid payment. The provider advertises no rate limits and instant access.
Documentation beyond the landing page is extremely sparse — the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema, and no example payloads available. The endpoint is live (returns a proper 402 challenge), but the exact request body format and response structure for historical stock data must be inferred or discovered experimentally.
Capabilities
Use cases
- —Retrieving historical price data for Union Pacific (UNP) stock for backtesting or analysis
- —Integrating pay-per-call stock data into autonomous trading agents without API key management
- —Building financial dashboards that pull historical equity data on demand
Fit
Best for
- —Agents or apps needing on-demand stock history without subscription commitments
- —Developers who want to pay per request in USDC on Base without account signup
- —Lightweight financial data retrieval where $0.02/call is cost-effective
Not for
- —High-frequency trading requiring sub-second latency and bulk data downloads
- —Users who need comprehensive documentation or guaranteed SLAs before integrating
- —Anyone without a Base-network USDC wallet or x402-compatible client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stocks/UNP/history \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-signed-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no OpenAPI spec, no request/response schema, no documentation, and no examples. The docs pages are all empty wallet-connect stubs. The listing is effectively a stub with confirmed liveness and pricing.
Warnings
- —No OpenAPI or schema available — request body format and response structure are unknown
- —All documentation pages (/docs, /pricing, /api, /README) render only 'Connect wallet' with no content
- —The specific stock endpoint (UNP/history) is not listed on the landing page; it may be part of an undocumented broader stocks API
- —No SLA, rate limit, or data source information provided
Citations
- —Endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/stocks/UNP/history
- —All APIs on lowpaymentfee.com are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/stocks/UNP/history