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 93) 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 pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request with no API keys, no rate limits, and no commitments. This particular endpoint falls under the finance category and appears to return performance metrics for a pre-defined portfolio. However, there is no public documentation describing the request body schema, response fields, or what "portfolio 93" represents. The docs, pricing, and API pages behind the site all resolve to a minimal "Connect wallet" prompt with no further detail.
Because no OpenAPI spec, request/response examples, or detailed documentation are available, the exact input parameters and output structure are unknown. The x402 challenge is live and well-formed, confirming the endpoint is operational and accepting payments. Agents should send a POST with an X-PAYMENT header containing a valid x402 payment proof to receive the response.
Capabilities
Use cases
- —Retrieving performance metrics for a tracked portfolio
- —Integrating portfolio performance data into dashboards or agents
- —Automated portfolio monitoring with per-call micropayments
Fit
Best for
- —Agents needing on-demand portfolio performance data without subscriptions
- —Developers experimenting with x402 pay-per-call finance APIs
- —Low-volume consumers who want no-commitment access to portfolio analytics
Not for
- —Users needing detailed API documentation or schema guarantees before integrating
- —High-frequency bulk data retrieval where per-call pricing adds up
- —Anyone requiring portfolio customization — this endpoint is fixed to portfolio ID 93
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/93/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page, and no explanation of what portfolio 93 is or what fields the response contains. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request body and response structure are unknown
- —The endpoint is hardcoded to portfolio ID 93 with no explanation of what this portfolio represents
- —All documentation pages (docs, pricing, API, README) return only a 'Connect wallet' prompt with no content
- —No examples of successful responses are available
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/93/performance
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/93/performance