Pay-per-call portfolio transactions endpoint on Base via x402, settled in USDC at $0.02/request.
What it does
This x402-enabled endpoint at lowpaymentfee.com provides access to portfolio transaction data (portfolio ID 96) via a POST request. 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). No API keys or rate limits are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The provider hosts a broader platform offering multiple API categories including data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities, all priced uniformly at $0.02 per request. This specific endpoint targets portfolio transactions, though the exact schema of the request body and response is not documented in the available crawl material.
The endpoint is confirmed live (returns HTTP 402 with a well-formed x402 challenge). However, documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. The input/output schemas, required POST body fields, and response format are unknown.
Capabilities
Use cases
- —Retrieving transaction records for a specific portfolio
- —Integrating portfolio transaction data into automated trading or analytics pipelines
- —Agent-driven portfolio monitoring with per-call micropayments
Fit
Best for
- —Developers needing keyless, pay-per-use portfolio transaction data
- —AI agents that can settle USDC payments on Base
- —Applications requiring no-commitment, no-subscription API access
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone needing portfolio IDs other than 96 (no evidence of parameterization)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/96/transactions \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The endpoint is confirmed live with a valid x402 challenge, but there is no documentation of request/response schemas, no OpenAPI spec, and all doc pages are empty. The listing is effectively a stub with only pricing and network details confirmed.
Warnings
- —No request body schema documented — required POST fields are unknown
- —No response schema or example available
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —Endpoint is scoped to portfolio ID 96 with no indication of how to access other portfolios
Citations
- —Endpoint returns HTTP 402 with x402 challenge requiring USDC on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/96/transactions
- —Max amount required is 20000 base units of USDC (6 decimals = $0.02)https://lowpaymentfee.com/api/v1/portfolios/96/transactions
- —Platform advertises $0.02/request pricing with no API keys, no rate limitshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/portfolios/96/transactions