x402-gated portfolio data endpoint on Base, pay $0.02 per request in USDC.
What it does
This endpoint at `/api/v1/portfolios/59` 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 data, and infrastructure utilities. The specific `/portfolios/59` resource is listed under "Premium API Access" but its exact data payload is not documented beyond the generic description. All endpoints on the platform share a uniform $0.02-per-request pricing model settled in USDC on the Base network.
The endpoint is live and returns a standard x402 challenge (HTTP 402) requiring an `X-PAYMENT` header. The payment scheme is "exact" with a `maxAmountRequired` of 20,000 base units of USDC (6 decimals), which equals $0.02. The asset contract is the canonical Base USDC (`0x8335…2913`). The endpoint accepts POST requests and returns `application/json`. No API keys or rate limits are advertised; access is gated purely by the x402 micropayment.
Documentation is extremely sparse. The docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what the `/portfolios/59` resource actually returns. The platform lists many endpoint categories (analytics, AI, finance, utilities) but provides no technical detail for any of them. Prospective users should be aware that the actual response schema and data quality are unknown.
Capabilities
Use cases
- —Fetching portfolio data (resource ID 59) via a single micropayment
- —Integrating pay-per-request data access into agent workflows without API key management
- —Programmatic access to premium data gated by on-chain USDC payments
Fit
Best for
- —Agents or scripts that need keyless, pay-as-you-go API access
- —Developers experimenting with x402 protocol integrations
- —Low-volume consumers who want no subscription commitments
Not for
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone requiring a well-documented response schema before calling
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/59 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is essentially no documentation: no OpenAPI schema, no request/response examples, no description of what '/portfolios/59' actually returns. The docs pages are empty beyond a wallet-connect prompt. Pricing is clear ($0.02/request in USDC on Base), but the lack of any payload documentation makes this effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content.
- —The actual response payload of /api/v1/portfolios/59 is completely undocumented; the data returned is unknown.
- —No OpenAPI or JSON schema is provided for request or response bodies.
- —The platform lists many endpoint categories but provides no technical detail for any of them — data quality and reliability are unverifiable.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/59
- —All endpoints on the platform are priced at $0.02 per request with no API keys, no rate limits, and no minimumshttps://lowpaymentfee.com
- —The USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/59
- —Docs, pricing, API, and README pages render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs