keyboard_type · Computer Use MCP Server MCP: Risk & Policy

WHAT IT DOES

What keyboard_type does on Computer Use MCP Server

AI agents invoke keyboard_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 keyboard_type needs a policy

Typing text into an active window is an external operation whose effects vary by context: it could fill forms, execute terminal commands, send messages, or modify documents. Since the server is for full desktop automation, misuse could cause significant unintended actions across any application.

From the tool's definition 'Type a text string character by character' — directly triggers keyboard input actions on the desktop, causing external side effects depending on the text typed and the currently focused application.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

keyboard_type Rate-limited

keyboard_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": {
    "keyboard_type": {
      "limits": [
        {
          "counter": "keyboard_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 keyboard_type

What does the keyboard_type tool do? +

Type a text string character by character. Handles Unicode characters. 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 keyboard_type? +

Register the Computer Use MCP Server MCP server in PolicyLayer and add a rule for keyboard_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 keyboard_type? +

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

Can I rate-limit keyboard_type? +

Yes. Add a rate_limit block to the keyboard_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 keyboard_type completely? +

Set action: deny in the PolicyLayer policy for keyboard_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 keyboard_type? +

keyboard_type is provided by the Computer Use MCP Server MCP server (syedazharmbnr1/computer-use-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.