MCP Filesystem Server Ultra

Safe, observable, and recoverable filesystem operations for AI agents

Why MCP Filesystem Ultra?

Version 4.5.29 — A safety-first MCP filesystem server for Claude Desktop and Claude Code. 20 tools (17 core + git + minify_js + help) with MCP spec-compliant annotations. Aliases are disabled to keep the tool surface small and predictable. v4.5.26+ adds outputSchema + structuredContent on read_file / write_file / edit_file / multi_edit for third-party MCP clients.

Safety by Default

Automatic backups, step-through undo, optimistic concurrency (expected_hash), accidental-rewrite guard, and risk assessment on every mutation.

Intelligent Operations

Automatic file-size detection and I/O strategy selection. No manual configuration needed.

Token Efficiency

Compact mode, range reads, and structured responses reduce token usage without sacrificing correctness.

Security Hardened

Go 1.26.5, path validation, symlink resolution, ADS/Unicode/reserved-name blocking, cmd.exe fallback removed, and govulncheck clean.

Key Features

Safe Editing by AI Agents

Automatic backups before every destructive operation with step-through undo
OCC / expected_hash to detect external changes and chain edits safely
Accidental-rewrite guard (allow_rewrite) prevents unintended full-file rewrites
Risk assessment on every edit — never blocked by risk level, always backed up
Soft-delete by default to recoverable trash

Observability & Control

Audit logging (--log-dir) with JSON Lines operation records
Enterprise dashboard for logs, metrics, backups, and trash recovery
Hooks (16 event types) for custom validation and workflows
Structured output on the 4 I/O core tools for strict MCP clients

Advanced Features

Pipeline Transformation: Multi-step file processing with variables and parallel execution
Advanced Backup: Persistent backups, chain undo, and searchable content recovery
Batch & Hooks: Atomic batch operations and pre/post hooks for custom commands
WSL Integration: Automatic path conversion and sync
Git Integration: 9 hardened git actions directly from the MCP server

Quick Start

# Build (Windows)
go build -ldflags="-s -w" -trimpath -o filesystem-ultra-v4.exe .

# Run with recommended settings
.\filesystem-ultra-v4.exe --compact-mode --cache-size 200MB --parallel-ops 8

Configure in Claude Desktop:

{
  "mcpServers": {
    "filesystem-ultra": {
      "command": "C:\\path\\to\\filesystem-ultra-v4.exe",
      "args": [
        "--compact-mode",
        "--cache-size", "200MB",
        "--parallel-ops", "8",
        "C:\\your\\allowed\\path\\"
      ]
    }
  }
}

Next Steps

Installation

Get up and running quickly

Core Concepts

Understand the architecture

API Reference

Explore all 20 tools

Safe Editing

Real-world editing protocol