computer_type · Computer Use MCP Server MCP: Risk & Policy

WHAT IT DOES

What computer_type does on Computer Use MCP Server

AI agents invoke computer_type to trigger actions in Computer Use MCP Server. 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 computer_type needs a policy

This tool injects keyboard input directly into the active application on an X11 desktop. It can type arbitrary text (commands, passwords, scripts, destructive instructions) into any focused window, making it a powerful execution vector. The actual effect depends entirely on where the cursor is focused — a terminal, a browser address bar, a file editor — giving it a high blast radius if misused.

From the tool's definition Type a text string at the current cursor position

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

computer_type Rate-limited

computer_type 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": {
    "computer_type": {
      "limits": [
        {
          "counter": "computer_type_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 MCP Server, so you can run agents against it safely.

FAQ

Questions about computer_type

What does the computer_type tool do? +

Type a text string at the current cursor position. It is categorised as a Execute tool in the Computer Use MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on computer_type? +

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

What risk level is computer_type? +

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

Can I rate-limit computer_type? +

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

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

computer_type is provided by the Computer Use MCP Server MCP server (sebastianbaltes/claude_code_computer_use_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.