CongressInvests vs Portfolio Optimizer

CongressInvests tracks U.S. congressional stock trades from official Senate EFD and House Clerk disclosures, refreshed every six hours, with per-ticker trade history, a global feed, and a Pro-only AI-generated trend narrative (sentiment plus notable member patterns, cached 24 hours per ticker). The core REST API is keyless for up to 100 requests/day; a $29/month Pro plan adds an X-Api-Key header for webhook alerts, the AI trend endpoint, and higher limits. It ships official Python and Node.js SDKs and markets itself against paid-only competitors like QuiverQuant and Unusual Whales.

Portfolio Optimizer is a free, no-signup Web API implementing modern-portfolio-theory algorithms — mean-variance and minimum-variance optimization, risk and performance analytics, backtesting, and factor-model tools — over JSON, so it can be called from Python, Excel, Google Sheets, or any HTTP client without an SDK. The homepage explicitly advertises free access with no registration required, and a live test against a real optimization endpoint (api.portfoliooptimizer.io) returned `Access-Control-Allow-Origin: *` on both a route-not-found and a malformed-payload response, confirming CORS is enabled; the same responses carry a `WWW-Authenticate: Key` header hinting at an optional key for higher throughput, though the observed default rate limit is a modest 1 request/second.