Portfolio performance data via x402 micropayment on Base network for $0.02/request.
What it does
This endpoint at lowpaymentfee.com provides portfolio performance data for a specific portfolio (ID 89) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (USD Coin) at a cost of $0.02 per request (20,000 base units with 6 decimals). No API keys or rate limits are required — access is granted per-request via the x402 payment protocol.
The provider, lowpaymentfee.com, hosts a broad catalog of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services, all priced at $0.02 per request. However, this specific endpoint (/api/v1/portfolios/89/performance) is not listed on the provider's public landing page among the advertised API categories. The endpoint is live and returns a valid x402 challenge (HTTP 402), but there is no documentation describing the request body schema, response format, or what "portfolio 89" refers to. The output schema in the challenge only specifies that it accepts HTTP POST and is discoverable, with no further detail on input parameters or response fields.
Without documentation or example responses, the exact data returned (e.g., time-series returns, risk metrics, benchmark comparisons) is unknown. Users should expect a JSON response related to portfolio performance but will need to experiment or contact the provider for specifics.
Capabilities
Use cases
- —Retrieving performance metrics for a specific investment portfolio
- —Integrating portfolio performance data into dashboards or agent workflows
- —Paying per-request for financial data without API key management
Fit
Best for
- —Agents or apps needing on-demand portfolio performance data with no subscription
- —Developers experimenting with x402 micropayment APIs on Base
- —Crypto-native workflows that can settle USDC payments programmatically
Not for
- —Users needing documented, well-specified financial data APIs with known schemas
- —Bulk historical portfolio data retrieval (pay-per-request model may be costly at scale)
- —Non-crypto users who cannot settle USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/89/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no documentation, no request/response schema, no examples, and the specific endpoint is not listed on the provider's own landing page. It is effectively a stub listing with only pricing and protocol details confirmed.
Warnings
- —No documentation available for this specific endpoint — request body and response schema are unknown.
- —This endpoint (/api/v1/portfolios/89/performance) is not listed among the provider's publicly advertised APIs.
- —The meaning of 'portfolio 89' is unexplained; it may be a demo or placeholder resource.
- —Crawled docs, API, pricing, and README pages all returned only 'Connect wallet' with no useful content.
Citations
- —The endpoint returns a valid x402 challenge with HTTP 402, accepting USDC on Base network with maxAmountRequired of 20000 base units.https://lowpaymentfee.com/api/v1/portfolios/89/performance
- —The provider advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base network.https://lowpaymentfee.com/api/v1/portfolios/89/performance