Delete a saved bookmark in the runner
AI agents call ui_delete_bookmark to permanently remove resources in UI Bridge MCP — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
This tool permanently removes stored bookmark data without the ability to undo the operation, fitting the Destructive category. While the blast radius is limited to bookmarks (not critical system data or financial assets), it represents permanent data loss that cannot be reversed, warranting medium severity. Confidence is high because the description is explicit about the destructive action.
From the tool's definition The tool name explicitly states 'delete_bookmark' and the description confirms it 'Delete a saved bookmark in the runner'. The verb 'delete' combined with 'bookmark' indicates irreversible removal of user data.
Attacks that exploit this kind of access
Delete a saved bookmark in the runner. It is categorised as a Destructive tool in the UI Bridge MCP MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the UI Bridge MCP server in PolicyLayer and add a rule for ui_delete_bookmark: 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 UI Bridge MCP. Nothing to install.
ui_delete_bookmark is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the ui_delete_bookmark 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.
Set action: deny in the PolicyLayer policy for ui_delete_bookmark. 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.
ui_delete_bookmark is provided by the UI Bridge MCP server (qontinui/ui-bridge-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →