rpc_scroll · Rpcclient MCP: Risk & Policy

WHAT IT DOES

What rpc_scroll does on Rpcclient

AI agents invoke rpc_scroll to trigger actions in Rpcclient. 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 rpc_scroll needs a policy

This tool triggers physical HID (Human Interface Device) swipe gesture actions on an iOS device, constituting an external operation/browser-like action. It executes real input events on a device, which could be misused to navigate UI in unintended ways, though the blast radius is moderate as scrolling alone doesn't directly cause data loss or financial harm.

From the tool's definition Scroll using HID swipe gestures

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

rpc_scroll Rate-limited

rpc_scroll 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": {
    "rpc_scroll": {
      "limits": [
        {
          "counter": "rpc_scroll_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 Rpcclient, so you can run agents against it safely.

FAQ

Questions about rpc_scroll

What does the rpc_scroll tool do? +

Scroll using HID swipe gestures. It is categorised as a Execute tool in the Rpcclient MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on rpc_scroll? +

Register the Rpcclient MCP server in PolicyLayer and add a rule for rpc_scroll: 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 Rpcclient. Nothing to install.

What risk level is rpc_scroll? +

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

Can I rate-limit rpc_scroll? +

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

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

rpc_scroll is provided by the Rpcclient MCP server (appknox/rpcclient-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.