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 74. It is part of a broader platform (lowpaymentfee.com) that offers a variety of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all gated via the x402 payment protocol on the Base network.
The specific endpoint `/api/v1/portfolios/74/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 (USDC uses 6 decimals). No API keys or rate limits are advertised; access is granted per-request upon valid x402 payment. The x402 challenge version is 1, with a payment timeout of 300 seconds.
Documentation is extremely sparse. The crawled docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive 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 74), but the exact fields, time ranges, or input parameters are unknown. The platform's landing page lists many other endpoints at $0.02 each across multiple categories, but this specific portfolio endpoint is not listed among them, making it unclear whether it is a demo, a specialized offering, or simply unlisted.
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-gated APIs
- —Automated financial analysis pipelines that pay per call
Not for
- —Users needing detailed API documentation or schema before integrating
- —Bulk historical portfolio data retrieval (no evidence of batch support)
- —Non-crypto-native users who cannot settle payments in USDC on Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/74/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming it accepts payments. However, there is no OpenAPI schema, no documentation of request/response fields, no examples, and the docs pages are empty. The endpoint path (portfolios/74) is hardcoded and not listed on the platform's landing page, raising questions about its intended use. Effectively a stub listing.
Warnings
- —No documentation available — all doc/API/pricing/README pages return only 'Connect wallet' with no content
- —No request or response schema provided; input parameters and output fields are completely unknown
- —This specific endpoint (/api/v1/portfolios/74/performance) is not listed among the platform's advertised APIs
- —Portfolio ID 74 is hardcoded in the path — unclear if other portfolio IDs are supported or how they are obtained
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/portfolios/74/performance
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/74/performance