Portfolio performance data via x402 micropayment on Base network, $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides portfolio performance data for a specific portfolio (ID 91) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 20,000 base units, which equals $0.02 per request (USDC uses 6 decimals).
The provider lowpaymentfee.com hosts a broad catalog of x402-gated APIs spanning data & analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all priced at $0.02 per call. This particular endpoint falls under the finance category. No API keys are required; access is granted instantly upon payment via the x402 protocol. The site advertises no rate limits and no minimum commitments.
Documentation is extremely sparse. The docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what fields the portfolio performance response contains or what input parameters the POST body expects. The endpoint is live (returns a valid 402 challenge), but the actual data contract is unknown.
Capabilities
Use cases
- —Retrieving performance metrics for a specific investment portfolio
- —Programmatic portfolio monitoring by AI agents paying per-request
- —Integrating portfolio performance data into dashboards or reports
Fit
Best for
- —Agents needing on-demand portfolio performance data without API key management
- —Micropayment-based access to financial data on Base network
- —Quick one-off portfolio performance lookups
Not for
- —Users needing detailed API documentation or schema guarantees before integration
- —High-frequency bulk data retrieval where per-request pricing adds up
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/91/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty stubs ('Connect wallet' only). The purpose of the endpoint can only be inferred from the URL path; actual input parameters and response fields are unknown.
Warnings
- —No API documentation available — docs, pricing, API, and README pages all return only 'Connect wallet' with no content
- —No OpenAPI or output schema provided; request body format and response structure are completely unknown
- —Portfolio ID 91 is hardcoded in the URL; unclear if other portfolio IDs are accessible or how they are discovered
- —Provider appears to be a generic x402 API storefront; unclear what actual data source backs portfolio performance
Citations
- —Endpoint returns 402 with x402 challenge requiring USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/91/performance
- —Maximum amount required is 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equaling $0.02https://lowpaymentfee.com/api/v1/portfolios/91/performance
- —Site advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Documentation pages (docs, pricing, API, README) contain only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs