clear_layer

THE RISK

Critical Risk

Why clear_layer needs a policy

Clearing a layer in a live presentation system like ProPresenter removes active content from display or playback immediately. This action is not simply a write/update but an irreversible removal of the live state of that layer (e.g., clearing the slide layer removes what is currently shown on screen). In a live production context, this could disrupt an ongoing service or event and cannot be easily undone.

From the tool's definition "Clear a specific layer" — clearing a layer removes/wipes the currently active content from that layer (audio, props, messages, announcements, slide, media, video_input)

Documented attack patterns abuse exactly the kind of access clear_layer gives an agent:

POLICY

How to control clear_layer

PolicyLayer is an MCP gateway — it sits between your AI agents and Propresenter, and nothing reaches the server without passing your rules. This is the rule we recommend for clear_layer:

policy.json

{
  "version": "1",
  "default": "deny",
  "hide": [
    "clear_layer"
  ]
}

clear_layer disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.

Create a free account and register Propresenter — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RESTRICT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Propresenter tools

Destructive messages_delete Delete a specific message Destructive props_clear Clear a specific prop from display Destructive props_delete Delete a specific prop Destructive props_delete_collection Delete a specific prop collection Destructive stage_delete_layout Delete a specific stage layout Execute clear_trigger_group Trigger a specific clear group Execute props_pause_auto_clear Pause auto-clear for a specific prop Execute timers_operation Perform a specific operation on a timer (start, stop, reset)

All 177 Propresenter tools →

Destructive tools on other servers

Android Forensics ADB MCP Server create_full_backup 0xarchive web3_revoke_key Frida Game Hacking MCP clear_scan cPanel MCP Server clear_spam_box

Go deeper

Critical-risk tools in Propresenter → Every critical-risk tool this server exposes, in one view.
All critical-risk MCP tools → Every critical-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Blast radius → How much damage one compromised or confused agent can do — and how to bound it.
Tool call approval → Approval gates on individual tool calls: auto-allow, prompt, or deny.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about clear_layer

What does the clear_layer tool do? +

Clear a specific layer (audio, props, messages, announcements, slide, media, video_input). It is categorised as a Destructive tool in the Propresenter MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.

How do I enforce a policy on clear_layer? +

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

What risk level is clear_layer? +

clear_layer is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit clear_layer? +

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

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

clear_layer is provided by the Propresenter MCP server (@alxpark/propresenter-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Propresenter tool call.

Start from Propresenter, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →