x402-gated account balance endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides an account balance lookup via the x402 payment protocol. The specific resource `/api/v1/accounts/110/balance` is described as "Premium API Access" and returns JSON. Payment is settled on the Base network using USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) with a maximum cost of $0.02 per request (20,000 base units at 6 decimals).
The broader lowpaymentfee.com platform advertises a suite of x402-gated APIs spanning data & analytics (metrics, reports, data export, insights), AI & machine learning (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request with no API keys, no rate limits, and no minimum commitments.
However, the specific endpoint being listed here — `/api/v1/accounts/110/balance` — is not documented among the advertised APIs on the landing page. Its exact response schema and purpose are unclear. The docs, pricing, and API pages all returned only a "Connect wallet" prompt with no additional documentation. The endpoint is confirmed live via a valid 402 challenge, but the lack of documentation or schema details limits confidence in what it actually returns.
Capabilities
Use cases
- —Querying account balance information via a pay-per-call model
- —Integrating x402-compatible payment flows into agent workflows
- —Accessing premium data without API key registration
Fit
Best for
- —Agents that support x402 payment protocol on Base
- —Use cases requiring no-signup, pay-as-you-go API access
- —Developers testing x402 micropayment integrations
Not for
- —Users needing detailed API documentation or response schemas before integrating
- —High-volume use cases where per-request pricing may not be economical
- —Anyone without USDC on the Base network
Quick start
# The endpoint requires an x402 payment header (USDC on Base).
# 1. Send a POST to get the 402 challenge:
curl -X POST https://lowpaymentfee.com/api/v1/accounts/110/balance
# 2. Parse the 402 response, construct an X-PAYMENT header with a signed USDC payment, and resend.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no response schema, and the specific endpoint path (/api/v1/accounts/110/balance) is not listed among the platform's advertised APIs. The docs/pricing/API pages are all empty beyond a wallet connect prompt. This is effectively a stub listing.
Warnings
- —The endpoint /api/v1/accounts/110/balance is not listed among the platform's advertised APIs — its purpose and response format are unknown.
- —All documentation pages (docs, pricing, API, README) returned only 'Connect wallet' with no usable content.
- —No OpenAPI spec, output schema, or example responses are available.
- —The platform lists many other endpoints but none match this specific path, raising questions about what this endpoint actually does.
Citations
- —The endpoint returns a 402 challenge requesting USDC on Base with maxAmountRequired of 20000 base unitshttps://lowpaymentfee.com/api/v1/accounts/110/balance
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/accounts/110/balance
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform lists APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com