middle_click · Computer Use Windows MCP: Risk & Policy

WHAT IT DOES

What middle_click does on Computer Use Windows

AI agents invoke middle_click to trigger actions in Computer Use Windows. 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 middle_click needs a policy

Performs a mouse click action on the Windows desktop at specified coordinates. This triggers external UI interactions whose effects depend entirely on what is under the cursor at those coordinates — could open links, close tabs, trigger application actions, etc. It is an Execute-class browser/desktop action with moderate blast radius depending on context.

From the tool's definition Middle-click (scroll-wheel click) at the given coordinates

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

middle_click Rate-limited

middle_click 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": {
    "middle_click": {
      "limits": [
        {
          "counter": "middle_click_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 Computer Use Windows, so you can run agents against it safely.

FAQ

Questions about middle_click

What does the middle_click tool do? +

Middle-click (scroll-wheel click) at the given coordinates. ${FRONTMOST_GATE_DESC}. It is categorised as a Execute tool in the Computer Use Windows MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on middle_click? +

Register the Computer Use Windows MCP server in PolicyLayer and add a rule for middle_click: 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 Computer Use Windows. Nothing to install.

What risk level is middle_click? +

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

Can I rate-limit middle_click? +

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

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

middle_click is provided by the Computer Use Windows MCP server (wimi321/windows-computer-use-skill). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.