copy_file · Claude File Management Server MCP: Risk & Policy

WHAT IT DOES

What copy_file does on Claude File Management Server

AI agents use copy_file to create or update resources in Claude File Management Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Claude File Management Server environment.

WHY IT NEEDS A POLICY

Why copy_file needs a policy

Copying a file is a reversible write operation: it creates/modifies data on the filesystem (the destination) without destroying the original or being irreversible. The blast radius is minimal — accidental copies waste storage but can be deleted. No code execution, financial impact, or permanent destruction occurs.

From the tool's definition Tool name 'copy_file' with description 'Copy file from source to destination.' — this creates a duplicate of a file, modifying the destination filesystem by adding new data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

copy_file Rate-limited

copy_file stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "copy_file": {
      "limits": [
        {
          "counter": "copy_file_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Claude File Management Server, so you can run agents against it safely.

FAQ

Questions about copy_file

What does the copy_file tool do? +

Copy file from source to destination. It is categorised as a Write tool in the Claude File Management Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on copy_file? +

Register the Claude File Management Server MCP server in PolicyLayer and add a rule for copy_file: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Claude File Management Server. Nothing to install.

What risk level is copy_file? +

copy_file is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit copy_file? +

Yes. Add a rate_limit block to the copy_file rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block copy_file completely? +

Set action: deny in the PolicyLayer policy for copy_file. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides copy_file? +

copy_file is provided by the Claude File Management Server MCP server (vipin1000/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.