MCP server for the IronCalc spreadsheet engine — create, read, edit, and save xlsx files via Model Context Protocol
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# ironcalc-mcp [](https://pypi.org/project/ironcalc-mcp/) [](https://pypi.org/project/ironcalc-mcp/) [](LICENSE) [](https://github.com/yolonir/ironcalc-mcp/actions/workflows/test.yml) MCP server for the [IronCalc](https://www.ironcalc.com/) spreadsheet engine. Create, read, edit, and save xlsx files through the Model Context Protocol. Built on the typed high-level API in [IronCalc 0.8.3](https://pypi.org/project/ironcalc/). It exposes workbook editing, formulas, styles, structure, names, conditional formatting, and xlsx persistence through MCP. ## Motivation I was really inspired by [paper.design](https://paper.design/)'s real-time MCP workflow, where exposing a design tool via MCP enables custom, extensible agent workflows that feel native rather than bolted on. Current AI-spreadsheet integrations (like Claude's cowork mode for Excel) add an unnecessary layer of abstraction - the agent writes Python code that manipulates Excel, instead of talking to the spreadsheet directly. This MCP server removes that indirection. Agents read cells, write formulas, and get evaluated results in one hop. No codegen middleman, no openpyxl glue scripts. Huge thanks to the [IronCalc](https://github.com/ironcalc/IronCalc) contributors - their Python SDK API is so clean that this entire MCP server is basically thin wrappers. The hard work is all theirs. **Current limitation:** the server works with an in-memory workbook - load a file, edit it, save it back. There's no real-time streaming to a running IronCalc UI yet. The engine already has a diff queue for syncing, so the plumbing is there. If IronCalc adds a WebSocket bridge to their web app, we can wire up live sync and get a true reactive workflow - agent edit…
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