Free deterministic REST and MCP tools for AI agents: ecommerce profit calculations, quotes, marketing metrics and developer utilities.
This tool is hosted on a railway.app platform subdomain, so it's listed as early-stage. When it moves to its own domain, re-submitting earns a full listing.
How people use Penny Engine
A small business owner can use Penny Engine to automate price quoting for custom product orders. The owner inputs product specifications and material costs through the API, and Penny Engine calculates the profit margin and generates a detailed quote for the customer. This streamlines the sales process and ensures consistent pricing.
An automated check confirmed the "Featured on PromptFrenzy" badge appears on penny-agent-api-production.up.railway.app and links back to this page without rel=nofollow or sponsored. The check re-runs daily for the first week and weekly thereafter — three consecutive failures move the listing to a 30-day grace window before public removal.
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