Pay-per-call portfolio transactions endpoint on Base via x402 (USDC, $0.02/request).
What it does
This x402-enabled endpoint at lowpaymentfee.com provides access to portfolio transaction data at the path `/api/v1/portfolios/86/transactions`. It accepts POST requests and is gated by the x402 payment protocol, settling in USDC on the Base network. Each call costs a maximum of 20,000 base units of USDC (i.e., $0.02 given USDC's 6 decimals), consistent with the site-wide flat pricing of $0.02 per request.
The provider, lowpaymentfee.com, hosts a broad catalog of pay-per-call APIs spanning data & analytics, AI/ML inference, finance & Web3, and infrastructure utilities — all priced at $0.02 per request with no API keys, no rate limits, and no commitments. The specific endpoint listed here targets portfolio transactions (portfolio ID 86), though the exact schema of the request body and response payload is not documented in the available crawl material. The x402 challenge confirms the endpoint is live, returns a proper 402 Payment Required response, and advertises USDC (contract 0x8335…2913) on Base as the accepted asset.
Because no OpenAPI spec, request/response schemas, or detailed documentation were found beyond the landing page summary, the actual fields accepted by the POST body and the structure of the returned transaction data remain unknown. Prospective callers should be aware that this is a relatively undocumented endpoint and may need to experiment or contact the provider for integration details.
Capabilities
Use cases
- —Fetching transaction history for a specific portfolio via a single paid API call
- —Integrating portfolio transaction data into automated trading or analytics pipelines
- —Agent-driven portfolio monitoring with per-call USDC micropayments
Fit
Best for
- —Developers wanting keyless, pay-per-call access to portfolio transaction data
- —AI agents that can settle x402 payments in USDC on Base
- —Users who prefer no-subscription, usage-based pricing
Not for
- —Users needing detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who need bulk/discounted pricing
- —Anyone requiring non-USDC or non-Base-network payment settlement
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/86/transactions \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is confirmed live via a valid 402 x402 challenge, and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and the purpose of this specific portfolio endpoint is only vaguely described as 'Premium API Access'. This is effectively a stub listing.
Warnings
- —No OpenAPI or request/response schema available — request body and response structure are unknown.
- —Documentation pages (/docs, /api, /pricing, /README) returned only 'Connect wallet' with no useful content.
- —The endpoint targets a hardcoded portfolio ID (86); it is unclear whether other portfolio IDs are available or how they are obtained.
- —The generic 'Premium API Access' description from the provider gives no detail about what transaction data is returned.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Base network.https://lowpaymentfee.com/api/v1/portfolios/86/transactions
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.https://lowpaymentfee.com/api/v1/portfolios/86/transactions
- —Site-wide pricing is $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com