How to Architect a Multi-Tenant MCP Server for Enterprise B2B SaaS

Orchestrating an AI agent on your laptop is deceptively easy. You define a persona, hand it a few Python functions, paste a vendor API key into a .env file, and watch the agent reason through tasks. But deploying that same agent into a production B2B SaaS environment exposes a massive architectural gap. If you’ve shipped a local Model Context Protocol (MCP) server with credentials baked into environment variables and now need to scale it to thousands of B2B customers, the gap between those two states is brutal.