onui_delete_annotation

THE RISK

Critical Risk

This tool permanently removes annotations without a stated undo mechanism. While the blast radius is limited to annotation data (not financial or system-critical), deletion is irreversible and destructive in nature, making it more severe than Write operations. An AI agent could maliciously or accidentally purge important UI annotations, hindering team workflows.

From the tool's definition Tool name contains 'delete' and description states 'Delete a single annotation by id' — an irreversible operation that removes data.

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

HOW TO CONTROL ONUI_DELETE_ANNOTATION

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

policy.json

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

onui_delete_annotation 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 onUI — 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

More onUI tools

Destructive onui_clear_page_annotations Delete all annotations for a specific page URL. Write onui_bulk_update_annotation_metadata Bulk update metadata for multiple annotations. Write onui_update_annotation_metadata Update metadata for a single annotation (status/intent/severity/comment). Read onui_get_annotations Get annotations for a specific page URL. Read onui_get_report Generate annotation report in compact/standard/detailed/forensic format. Read onui_list_pages List pages that have onUI annotations in the local store. Read onui_search_annotations Search annotations across the local store with optional filters.

All 8 onUI tools →

Destructive tools on other servers

Frida Game Hacking MCP clear_scan MegaMemory remove_concept Frida Agent MCP kill_app 1MCP Server mcp_uninstall

Go deeper

Critical-risk tools in onUI → 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.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

What does the onui_delete_annotation tool do? +

Delete a single annotation by id. It is categorised as a Destructive tool in the onUI 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 onui_delete_annotation? +

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

What risk level is onui_delete_annotation? +

onui_delete_annotation 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 onui_delete_annotation? +

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

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

onui_delete_annotation is provided by the onUI MCP server (onllm-dev/onui). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every onUI tool call.

Deterministic rules across all 8 onUI tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

GOVERN ONUI →

Free to start. No card required.

8 onUI tools catalogued and risk-classified — across an index of 42,500+ MCP servers.

// WHAT ONUI_DELETE_ANNOTATION ON ONUI DOES

// THE RISK

// HOW TO CONTROL ONUI_DELETE_ANNOTATION

// EXPLORE