File Modifier MCP Server

Connect File Modifier to Claude, Cursor or any other MCP client and it stops being a tab you switch to. Enables modification of files through a Model Context Protocol server. The file modifier mcp server is what makes that connection.

What the server does

A Model Context Protocol server for file modifications. This server provides functionality to modify files through Claude or other AI assistants using MCP.

• Add content at specific line numbers
• Replace existing content
• Delete content
• UTF-8 encoding support

Installation

The server ships on npm as mcp-server-file-modifier, so your MCP client can launch it on demand — there is no separate build step. Add the server block to your client's configuration, restart it, and the tools register themselves.

Available tools

The toolset is worth reading before you wire it up, because it tells you what the integration is really for:

• add — Add new content at a specific line
• replace — Replace content matching a target
• delete — Delete content matching a target

Worth knowing first

• It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
• Keep per-call confirmation enabled while you learn its behaviour; it is the cheapest safeguard you have.

Where it fits

Plenty of developer tooling servers cover similar ground. The differences that matter in practice are scope of access and how much setup stands between you and a working tool call. File Modifier's toolset — add, replace, delete — is a fair guide to whether it matches your workflow. It is maintained by jpinillagoshawk; worth a glance at recent repository activity before you build anything load-bearing on it.

We check each listing at SyncDev against the project's documentation before it goes live — if something here drifts out of date, it is a bug worth reporting.