Quick context: I run GitDealFlow , an MCP server + dataset that tracks GitHub commit-velocity signals across ~100 venture-backed startups. Six free read-only tools, ~700 npm downloads in the first three weeks, listed on Glama and the official MCP registry.

We just shipped a seventh tool: get_deep_signal . It's paid — €0.19 per call, sold in 100-credit packs at €19. The other six tools stay free forever.

This post is about why we chose per-request over a monthly subscription, and how the implementation actually looks. tl;dr: when your customer is an agent making programmatic API calls, the SaaS rulebook stops working.

The framing

Marc Benioff announced "Salesforce Headless 360" on April 17 — entire Salesforce + Agentforce + Slack platforms exposed as APIs, MCP, and CLI. "The API is the UI now."

That made it official: the new customer for SaaS-shaped data products is an agent , not a human clicking through a dashboard.…