Excel MCP Server (FsOpenXmlDsl) — Claude Code MCP server
Decompiles .xlsx workbooks into standalone F# or C# scripts, XML, and JSON. It helps agents read existing spreadsheets and construct new files from structured schemas.
Open on GitHubWhat Excel MCP Server (FsOpenXmlDsl) does
Most spreadsheet libraries only write files imperatively. This server works in both directions. It parses existing .xlsx or .xlsm files into a typed data model, then decompiles that model into readable C# or F# scripts. You can run those scripts to recreate the identical workbook.
The engine also maps workbooks to and from plain XML and JSON. Through the Model Context Protocol, it exposes tools like generate_csharp_script, generate_fsharp_script, generate_xml, create_workbook_from_xml, and corresponding JSON handlers. Supported structures include cell formatting, data validations, comments, tables, sparklines, and charts.
VBA macros are preserved strictly as raw vbaProject.bin bytes rather than deconstructed code. Running the server requires either the .NET toolchain or a standalone pre-built executable from the repository releases.
What it helps with
- Decompile
.xlsxspreadsheets into standalone C# or F# scripts - Build new Excel workbooks directly from JSON or XML structures
- Inspect existing styles, tables, and formulas via structured representations
- Generate reproducible spreadsheet code without writing manual OpenXML calls
Example prompts for the agent
- Convert
invoice.xlsxinto a standalone C# script usinggenerate_csharp_script. - Create a new workbook from
payload.jsonviacreate_workbook_from_json. - Export the structure of
report.xlsxinto XML usinggenerate_xml.
How to install Excel MCP Server (FsOpenXmlDsl)
Install
The MCP registry has no launch command for it: see the repository README
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Excel MCP Server (FsOpenXmlDsl)
How to install Excel MCP Server (FsOpenXmlDsl) in Claude Code?
Install the CLI tool using dotnet tool install -g Kookerella.FsOpenXmlDsl.Mcp or download a pre-built binary from the releases page, then add the fsopenxmldsl-mcp executable to your platform MCP configuration.
What does Excel MCP Server (FsOpenXmlDsl) do?
It decompiles .xlsx and .xlsm workbooks into standalone F# or C# scripts and enables bidirectional conversion between spreadsheets, XML, and JSON.
Is the .NET runtime required to run this tool?
No, the .NET SDK is optional. If you do not have .NET installed, you can download a standalone binary for your operating system directly from the project releases.
