split_pane · Iterm2 MCP: Risk & Policy

WHAT IT DOES

What split_pane does on Iterm2

AI agents invoke split_pane to trigger actions in Iterm2. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why split_pane needs a policy

Based on the server context and sibling tools (create_tab, create_window), split_pane likely creates a new terminal pane split within iTerm2. This is a Write/Execute-level action that creates a new terminal session environment.

From the tool's definition Tool name 'split_pane' on a server that provides 'full control over iTerm2 terminal sessions' and can 'manage windows, tabs, and panes'. Description is empty.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

split_pane Rate-limited

split_pane stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "split_pane": {
      "limits": [
        {
          "counter": "split_pane_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Iterm2, so you can run agents against it safely.

FAQ

Questions about split_pane

What does the split_pane tool do? +

split_pane. It is categorised as a Execute tool in the Iterm2 MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on split_pane? +

Register the Iterm2 MCP server in PolicyLayer and add a rule for split_pane: 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 Iterm2. Nothing to install.

What risk level is split_pane? +

split_pane is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit split_pane? +

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

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

split_pane is provided by the Iterm2 MCP server (lorencarvalho/iterm2-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.