set_session_name · Iterm2 MCP: Risk & Policy

WHAT IT DOES

What set_session_name does on Iterm2

AI agents use set_session_name to create or update resources in Iterm2 — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Iterm2 environment.

WHY IT NEEDS A POLICY

Why set_session_name needs a policy

This tool creates or modifies session metadata reversibly. It is a Write operation because it changes iTerm2 session properties in a way that can be easily undone by setting the name to a different value. The blast radius is minimal—renaming a session does not affect command execution, data integrity, or system state.

From the tool's definition Tool description: 'Set the title/name of an iTerm2 session.' This modifies metadata (session name/title) but does not alter terminal content, execute commands, or delete data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_session_name Rate-limited

set_session_name 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": {
    "set_session_name": {
      "limits": [
        {
          "counter": "set_session_name_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 Iterm2, so you can run agents against it safely.

FAQ

Questions about set_session_name

What does the set_session_name tool do? +

Set the title/name of an iTerm2 session. It is categorised as a Write tool in the Iterm2 MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_session_name? +

Register the Iterm2 MCP server in PolicyLayer and add a rule for set_session_name: 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 set_session_name? +

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

Can I rate-limit set_session_name? +

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

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

set_session_name 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.