x402-gated transaction receipt endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource (transaction ID 27) behind an x402 paywall. It is part of a broader platform that advertises multiple API categories — data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all gated via x402 micropayments on the Base network using USDC.
The specific endpoint `/api/v1/transactions/27/receipt` accepts POST requests and returns JSON. The x402 challenge indicates a maximum payment of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 per request given USDC's 6 decimal places. This aligns with the site's advertised flat pricing of $0.02 per request across all endpoints. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
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 platform markets itself as having no API keys, no rate limits, and instant access, but the actual functionality behind each endpoint is undocumented. The endpoint is confirmed live (402 challenge captured successfully).
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 27 via a single micropayment
- —Demonstrating x402 protocol integration for pay-per-call APIs
- —Agent-driven programmatic access to receipts without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need keyless, pay-per-call API access on Base
- —Projects requiring USDC-settled micropayment workflows
Not for
- —Production use requiring documented request/response schemas
- —Bulk or high-volume receipt retrieval (no documented batch support)
- —Users who need fiat payment options or non-crypto settlement
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/27/receipt \
-H "X-PAYMENT: <x402-payment-header>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation is essentially nonexistent — docs/pricing/API pages all show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, and no examples. The specific purpose of this particular receipt endpoint (transaction 27) is unclear. Score reflects a confirmed-live endpoint with minimal usable information.
Warnings
- —No documentation available — all doc pages render only 'Connect wallet'
- —No OpenAPI or schema definition for request or response payloads
- —The endpoint path references a specific transaction ID (27); unclear if this is parameterized or fixed
- —No examples of actual response data available
- —Platform advertises many endpoint categories but none have documented behavior
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/27/receipt
- —The platform advertises $0.02 per request flat pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/27/receipt
- —The site lists endpoints across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com