fs_rename · Mcp Ssh Tool MCP: Risk & Policy

WHAT IT DOES

What fs_rename does on Mcp Ssh Tool

AI agents use fs_rename to create or update resources in Mcp Ssh Tool — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mcp Ssh Tool environment.

WHY IT NEEDS A POLICY

Why fs_rename needs a policy

Renaming and moving files are Write operations because they modify data organization reversibly. Severity is high because autonomous SSH execution on remote systems could rename critical files (application configs, system files) causing service failures or data inaccessibility. The context of autonomous SSH operations without manual prompts increases blast radius if an agent makes incorrect rename decisions.

From the tool's definition Tool description states 'Renames or moves a file/directory'. These operations modify filesystem state reversibly (can be undone by renaming back or moving to original location), but do not delete data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

fs_rename Rate-limited

fs_rename 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": {
    "fs_rename": {
      "limits": [
        {
          "counter": "fs_rename_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 Mcp Ssh Tool, so you can run agents against it safely.

FAQ

Questions about fs_rename

What does the fs_rename tool do? +

Renames or moves a file/directory. It is categorised as a Write tool in the Mcp Ssh Tool MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on fs_rename? +

Register the Mcp Ssh Tool MCP server in PolicyLayer and add a rule for fs_rename: 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 Mcp Ssh Tool. Nothing to install.

What risk level is fs_rename? +

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

Can I rate-limit fs_rename? +

Yes. Add a rate_limit block to the fs_rename 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 fs_rename completely? +

Set action: deny in the PolicyLayer policy for fs_rename. 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 fs_rename? +

fs_rename is provided by the Mcp Ssh Tool MCP server (skot/mcp-ssh-tool). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.