# Engineering articles from **Flex**

June 23, 2026  
## [MCP Use Cases: How We Built a Custom MCP Server for a Non-Technical Merchant](/content/blog/custom-mcp-server-non-technical-merchants/index.html)  
A real MCP use case: how Flex built a custom MCP server so a non-technical merchant could manage subscriptions and payments by chatting with an AI, with no API, no dashboard, and no support tickets.  
  
Roni Khudanyan  
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May 21, 2026  
## [Introducing Flex MCP: Connect Your AI Assistant Directly to Flex](/content/blog/introducing-flex-mcp-connect-ai-assistants-to-flex/index.html)  
Flex MCP is a new MCP server that connects AI assistants like Claude, Cursor, Codex, and Windsurf directly to your Flex account, so you can look up orders, reconcile payments, manage billing, and run reports without leaving your coding or productivity tools.  
  
Kevin Wentland  
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March 26, 2026  
### [The Flex AI Investigation Agent for HSA/FSA Payments](/content/blog/the-flex-ai-investigation-agent-for-hsa-fsa-payments/index.html)  
We built a Slack agent that can trace a transaction end to end—and, when it finds a bug, open a pull request with a proposed fix.  
  
Varsha Parthasarathy  
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February 11, 2026  
### [Securing Flex Checkout Order Confirmations with Webhooks](/content/blog/secure-flex-checkout-using-webhooks/index.html)  
Our engineering team explains how to listen to and verify webhooks in your Flex-powered checkout to secure order confirmations and reduce fraudulent orders.  
  
David Barratt  
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