x402-gated portfolio data endpoint on Base, pay $0.02 per request in USDC.
What it does
This endpoint at `/api/v1/portfolios/88` is part of the lowpaymentfee.com platform, which offers a collection of x402-protocol pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. The specific `/portfolios/88` resource is listed under "Premium API Access" but its exact data payload is undocumented — the crawled site provides no schema or example response for this particular route. The broader platform advertises a uniform $0.02 per request pricing model with no API keys, no rate limits, and instant access.
Payment is settled on the Base network using USDC (contract `0x8335…2913`) via the x402 exact-payment scheme. The probe confirmed a live 402 challenge with `maxAmountRequired` of 20,000 base units, which at 6 decimals equals $0.02 USD — consistent with the site's advertised pricing. The endpoint accepts POST requests and returns `application/json`. No OpenAPI spec, detailed documentation, or example responses were found; the docs, pricing, API, and README pages all rendered only a "Connect wallet" prompt with no substantive content.
Because the actual response schema and the meaning of "portfolios/88" are unknown, agents should treat this as a low-documentation endpoint. It is live and correctly implements the x402 payment challenge, but callers will need to experiment or contact the provider to understand the request body format and response structure.
Capabilities
Use cases
- —Fetching portfolio data behind a micropayment wall
- —Programmatic access to premium data without subscription or API key
- —Agent-driven data retrieval with per-call USDC payment on Base
Fit
Best for
- —Agents that can settle x402 payments in USDC on Base
- —One-off or low-volume data requests where subscription APIs are overkill
- —Developers exploring x402 pay-per-request patterns
Not for
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —High-volume consumers who would prefer bulk or subscription pricing
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/88 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no documentation, no OpenAPI spec, no example request/response, and no explanation of what 'portfolios/88' actually returns. The docs pages are empty. This is effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content.
- —The response schema for /api/v1/portfolios/88 is completely unknown; no examples or field descriptions exist.
- —The meaning of 'portfolios/88' (what data it returns, what POST body it expects) is undocumented.
- —The broader platform lists many endpoints but none have detailed docs; quality of all services is unverifiable.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/portfolios/88
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/88
- —Docs, pricing, API, and README pages render only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs