Portfolio performance data via x402 micropayment on Base network, $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com returns portfolio performance data for portfolio ID 59. It is part of a broader platform (lowpaymentfee.com) that offers dozens of pay-per-call API endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all gated behind the x402 payment protocol on the Base network.
The specific endpoint `/api/v1/portfolios/59/performance` accepts POST requests and returns JSON. Payment is settled in USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base) at a maximum cost of 20,000 base units, which equals $0.02 USD (USDC uses 6 decimals). The x402 challenge was successfully captured, confirming the endpoint is live. No API keys or rate limits are advertised; access is granted purely through per-request micropayment.
Documentation is extremely sparse. The crawled docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no description of request parameters, and no example of the response payload. The endpoint path suggests it returns performance metrics for a specific portfolio (ID 59), but the exact fields, supported query parameters, and response structure are unknown. The platform's landing page lists the endpoint under "Finance & Web3" but the specific `/portfolios/59/performance` path is not listed among the advertised endpoints, making it unclear whether this is a demo, a user-specific resource, or a generally useful public endpoint.
Capabilities
Use cases
- —Retrieving performance metrics for a specific investment portfolio
- —Integrating portfolio performance data into dashboards or analytics pipelines
- —Agent-driven portfolio monitoring with per-call micropayments
Fit
Best for
- —Developers needing pay-per-call portfolio data without API key management
- —AI agents that can settle x402 payments on Base
- —Users who want low-cost, commitment-free access to financial performance data
Not for
- —Users needing documented, well-specified API contracts with known response schemas
- —Bulk data retrieval where per-request pricing would be expensive at scale
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/59/performance
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment on Base to access.Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no request/response examples, and the specific portfolio endpoint is not even listed on the provider's own landing page. The purpose and output of this endpoint are largely unknown.
Warnings
- —No API documentation available — docs, pricing, and README pages all return only a wallet-connect prompt
- —No OpenAPI or request/response schema provided; request parameters and response structure are completely unknown
- —The endpoint path references a specific portfolio ID (59), which may be a demo or user-specific resource rather than a generally useful public API
- —The /portfolios/ path is not listed among the provider's advertised endpoints on the landing page
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/portfolios/59/performance
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/59/performance
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages returned only a Connect wallet prompt with no substantive contenthttps://lowpaymentfee.com/docs