excel-mcp

An MCP server for safe .xlsx inspection and controlled workbook writes.

Status

This is an MVP. It supports workbook inspection, sheet/schema discovery, reads, search, simple filtering and numeric aggregation, plus preview-based writes. Writes are guarded by workspace confinement, SHA-256 compare-and-swap, a per-workbook lock, backup, temporary-file save, re-open verification, atomic replacement and JSONL audit logging.

Macro-enabled workbooks, external links, charts, formatting operations and non-.xlsx files are intentionally out of scope.

Quick start from GitHub

You do not need to clone this repository. Install uv once, then configure your MCP client to run the latest version directly from GitHub.

The command is:

uvx --from git+https://github.com/Matsu132/excel-mcp.git excel-mcp

The only local setting you need is the folder containing the Excel files:

EXCEL_MCP_WORKSPACE=/Users/your-name/Documents/Excel

This keeps Excel data on your computer. The public GitHub repository provides the server code and dependencies; it does not upload your workbooks.

Developer installation

uv sync

Set the workbook directory that the server is allowed to access:

export EXCEL_MCP_WORKSPACE="/absolute/path/to/workbooks"

The server accepts only .xlsx files inside this directory. Relative paths are resolved from this workspace.

Starting the server

This server uses MCP over stdio. The command to register in an MCP client is:

uvx --from git+https://github.com/Matsu132/excel-mcp.git excel-mcp

For a direct local check:

EXCEL_MCP_WORKSPACE="/absolute/path/to/workbooks" uv run excel-mcp

Keep the process running when the client starts it; MCP clients normally manage the process lifecycle automatically.

Claude Desktop

Add the following entry to Claude Desktop's MCP configuration file. Replace the paths with absolute paths on your machine.

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "excel-mcp": {
  "command": "uvx",
      "args": ["--from", "git+https://github.com/Matsu132/excel-mcp.git", "excel-mcp"],
      "env": {
        "EXCEL_MCP_WORKSPACE": "/Users/your-name/Documents/Excel"
      }
    }
  }
}

Restart Claude Desktop after saving the file. The excel_* tools should then appear in the MCP tools list.

OpenAI-compatible clients

For an OpenAI application, Agent SDK, or other client that supports local MCP stdio servers, register the same command as a local MCP server:

{
  "name": "excel-mcp",
  "command": "uvx",
  "args": ["--from", "git+https://github.com/Matsu132/excel-mcp.git", "excel-mcp"],
  "env": {
    "EXCEL_MCP_WORKSPACE": "/Users/your-name/Documents/Excel"
  }
}

The exact configuration key varies by product. Use the product's local MCP or stdio server setting and map it to command, args, and env above. If the client only supports remote MCP endpoints, this repository needs an HTTP transport deployment before it can be used directly.

Other MCP clients

Clients such as Cursor, VS Code MCP extensions, Cline, Windsurf, and MCP Inspector generally accept the same stdio definition. Use:

Command: uvx
Arguments: --from git+https://github.com/Matsu132/excel-mcp.git excel-mcp
Environment: EXCEL_MCP_WORKSPACE=/Users/your-name/Documents/Excel

For MCP Inspector, run:

EXCEL_MCP_WORKSPACE="/absolute/path/to/workbooks" uv run mcp dev src/excel_mcp/server.py

Japanese documentation

日本語のセットアップ手順は README_JAPANESE.md を参照してください。

MCP SDK

This project uses the official MCP Python SDK v2 with MCPServer and @mcp.tool(). The default transport is stdio for local MCP clients. See the official v2 documentation for the SDK API and transport details.