x402-gated transaction receipt endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a specific transaction receipt (transaction ID 185) behind an x402 paywall. The broader lowpaymentfee.com platform advertises a suite of pay-per-request APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 data (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, settled in USDC on the Base network via the x402 protocol.
The specific endpoint probed (/api/v1/transactions/185/receipt) returns a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this equates to $0.02 per call, consistent with the site's advertised pricing. Payment is made via the x402 "exact" scheme, requiring no API keys, no rate limits, and no upfront commitments — just an X-PAYMENT header with a valid payment proof.
Documentation is extremely sparse. The /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema documentation, and no examples of what the receipt payload actually contains. The endpoint accepts POST requests and returns application/json, but the structure of both the request body and the response is unknown.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 185 via programmatic x402 payment
- —Demonstrating x402 protocol integration with USDC on Base
- —Agent-driven pay-per-request data retrieval without API key management
Fit
Best for
- —Developers experimenting with x402 protocol payments on Base
- —Agents that need keyless, pay-per-call API access settled in USDC
- —Prototyping micropayment-gated API workflows
Not for
- —Production workloads requiring documented request/response schemas
- —Users who need free or subscription-based API access
- —Anyone needing bulk or batch transaction receipt retrieval
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/185/receipt
# Returns 402 with x402 challenge; include X-PAYMENT header with valid USDC payment proof on Base to access the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge at $0.02/call in USDC on Base. However, there is no OpenAPI spec, no documentation of request or response schemas, and the docs pages are empty. The specific purpose of this particular receipt endpoint (transaction 185) is unclear, and the broader platform's many advertised endpoints lack any technical documentation.
Warnings
- —No OpenAPI or schema documentation available for any endpoint on the platform
- —All documentation pages (/docs, /api, /pricing, /README) render only a 'Connect wallet' prompt with no content
- —The endpoint is for a specific transaction ID (185); it is unclear whether this is a demo or a real resource
- —Request body schema and response payload structure are completely unknown
- —The platform advertises many endpoints (AI, finance, utils) but none have documented schemas
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/185/receipt
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/185/receipt
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Platform advertises APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages render only a Connect wallet prompt with no substantive contenthttps://lowpaymentfee.com/docs