session_send · It2 MCP: Risk & Policy

WHAT IT DOES

What session_send does on It2mcp

AI agents invoke session_send to trigger actions in It2mcp. 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 session_send needs a policy

Sending text to a terminal session can stage arbitrary commands for execution. Even without pressing Enter, the text is placed in an active terminal buffer and could be completed or executed by subsequent actions. The blast radius is high as it can inject commands into any active terminal session, potentially affecting files, processes, and system state.

From the tool's definition "Send text to an iTerm2 session" — sends arbitrary text/commands to a terminal session

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

session_send Rate-limited

session_send 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": {
    "session_send": {
      "limits": [
        {
          "counter": "session_send_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 It2mcp, so you can run agents against it safely.

FAQ

Questions about session_send

What does the session_send tool do? +

Send text to an iTerm2 session without pressing Enter. It is categorised as a Execute tool in the It2mcp MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on session_send? +

Register the It2 MCP server in PolicyLayer and add a rule for session_send: 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 It2mcp. Nothing to install.

What risk level is session_send? +

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

Can I rate-limit session_send? +

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

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

session_send is provided by the It2 MCP server (urjitbhatia/it2mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.