shell_set_default_workdir · MCP Shell Server MCP

WHAT IT DOES

What shell_set_default_workdir does on MCP Shell Server

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

WHY IT NEEDS A POLICY

Why shell_set_default_workdir needs a policy

This tool modifies configuration state (the default working directory) in a reversible manner. It is not Read (it changes state), not Execute (it does not run commands or code—it only sets a parameter), not Destructive (the change is reversible by setting a different directory), and not Financial. Write is the appropriate category.

From the tool's definition Tool description states it 'Set[s] the default working directory for command execution' — a modification operation that changes execution context but does not delete data or execute arbitrary code.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

shell_set_default_workdir Rate-limited

shell_set_default_workdir 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": {
    "shell_set_default_workdir": {
      "limits": [
        {
          "counter": "shell_set_default_workdir_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 Shell Server, so you can run agents against it safely.

FAQ

Questions about shell_set_default_workdir

What does the shell_set_default_workdir tool do? +

Set the default working directory for command execution. It is categorised as a Write tool in the MCP Shell 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 shell_set_default_workdir? +

Register the MCP Shell Server MCP server in PolicyLayer and add a rule for shell_set_default_workdir: 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 Shell Server. Nothing to install.

What risk level is shell_set_default_workdir? +

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

Can I rate-limit shell_set_default_workdir? +

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

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

shell_set_default_workdir is provided by the MCP Shell Server MCP server (mako10k/mcp-shell-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.