Portfolio performance data via x402 micropayment on Base network, $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns portfolio performance data for portfolio ID 18. It is part of a broader platform offering various pay-per-call APIs across data analytics, AI/ML, finance, and infrastructure categories. The endpoint uses the x402 payment protocol, settling in USDC on the Base network. Each request costs $0.02 (20,000 base units of USDC with 6 decimals). No API keys, rate limits, or subscriptions are required — callers simply attach an x402 payment header to each POST request.
The specific endpoint `/api/v1/portfolios/18/performance` is not listed on the provider's landing page among the advertised API categories, which focus on analytics, AI, finance, and utility endpoints. This suggests it may be a specialized or less-documented route. The response MIME type is `application/json`. No request body schema or response schema documentation was found beyond the x402 challenge metadata. The platform's docs, pricing, and API pages all returned minimal content (just a "Connect wallet" prompt), so detailed usage instructions are unavailable.
The endpoint is confirmed live — it returns a proper x402 challenge (HTTP 402) with version 1 of the protocol, accepting exact-scheme payments to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using USDC (`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`) on Base. The maximum timeout for payment settlement is 300 seconds.
Capabilities
Use cases
- —Retrieving performance metrics for a specific investment portfolio
- —Integrating portfolio performance data into dashboards or analytics tools
- —Agent-driven portfolio monitoring with per-call micropayments
- —Automated financial reporting pipelines
Fit
Best for
- —Agents or apps needing on-demand portfolio performance data without subscriptions
- —Developers experimenting with x402 micropayment-gated APIs
- —Low-volume consumers who prefer pay-per-request over monthly plans
Not for
- —Users needing detailed API documentation or request/response schemas before integrating
- —High-frequency bulk data consumers who need negotiated pricing or rate guarantees
- —Anyone requiring portfolio IDs other than 18 (no evidence other IDs are supported at this path)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/18/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation for request parameters, response schema, or what 'portfolio 18 performance' actually contains. The docs/pricing/API pages are all empty beyond a wallet-connect prompt. This is effectively a stub listing with confirmed liveness.
Warnings
- —No request body schema or response schema documented anywhere
- —The specific endpoint /api/v1/portfolios/18/performance is not listed among the provider's advertised APIs on the landing page
- —All documentation pages (docs, pricing, API, README) returned only a 'Connect wallet' prompt with no actual content
- —Unknown what data 'portfolio 18 performance' returns — no sample response available
- —Cannot confirm whether other portfolio IDs are valid
Citations
- —The endpoint returns a valid x402 challenge with USDC on Base, maxAmountRequired 20000 (=$0.02)https://lowpaymentfee.com/api/v1/portfolios/18/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 address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/portfolios/18/performance
- —Docs, pricing, API, and README pages all show only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs