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 a specific portfolio (ID 20) 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 an exact-scheme micropayment 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 market data, and infrastructure utilities — all priced at $0.02 per call. This particular endpoint sits under the finance category and appears to deliver performance metrics for a pre-defined portfolio. No API keys or rate limits are advertised; access is granted purely through the x402 payment header.
Documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema, and no example payloads available from the crawl. The exact fields returned by the portfolio performance endpoint are unknown and must be discovered by making a paid request.
Capabilities
Use cases
- —Fetching performance metrics for a tracked portfolio via automated agent
- —Integrating portfolio performance data into a dashboard without API key management
- —Pay-per-call access to financial portfolio analytics from an AI agent
Fit
Best for
- —Agents needing on-demand portfolio performance data without subscription commitments
- —Developers prototyping finance dashboards who want instant API access
- —x402-native workflows on Base network settling in USDC
Not for
- —Users who need detailed API documentation or response schema before purchasing
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone needing portfolio performance for arbitrary portfolio IDs (this endpoint is fixed to portfolio 20)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/20/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no example payloads. The purpose of the endpoint can only be inferred from its URL path.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —Endpoint is hardcoded to portfolio ID 20; unclear if other portfolio IDs are supported
- —Provider hosts many diverse API categories (AI, analytics, finance, utils) all at $0.02 — unclear what backing services actually power these endpoints
Citations
- —The x402 challenge requires 20,000 base units of USDC on Base network per requesthttps://lowpaymentfee.com/api/v1/portfolios/20/performance
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/portfolios/20/performance
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The endpoint accepts POST method and returns application/jsonhttps://lowpaymentfee.com/api/v1/portfolios/20/performance