Claude in Excel can connect to your backend APIs through MCP. You add your MCP server once under Claude AI -> Settings -> Connectors -> Custom Connectors (paste the MCP server URL); Claude in Excel then picks it up, and you ask in natural language from inside the sheet - it hits the backend and brings results back.
TigZig ran this across three of its own public MCP servers: pull 3 years of Yahoo Finance prices and build a rolling-returns model, generate a technical-analysis PDF/HTML report, and run a multi-security risk comparison - all from Excel chat. One caveat: it is weak at writing large datasets to cells (context bloat), so guide it to pull and write in smaller chunks.
This is different from xlwings Lite, which is pure Python in Excel (see the "which tool" FAQ). Guide: https://www.tigzig.com/post/claude-in-excel-mcp-connector-talk-to-backends. Claude-for-Analytics hub: https://www.tigzig.com/claude-for-analytics. MCP servers: https://www.tigzig.com/apis.
Building something like this? How I work covers the rates, the availability and what I take on.