AI agents call delete_stairs to permanently remove resources in IFC Bonsai MCP — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
The tool name explicitly uses 'delete', which signals an irreversible operation that destroys data in the IFC model. While the description is empty (lowering confidence slightly), the clear destructive semantics of the verb place this in the Destructive category, the most severe among the non-Financial options.
From the tool's definition Tool name is 'delete_stairs' with no description provided. The verb 'delete' indicates irreversible removal of data (stair objects in an IFC model).
Documented attack patterns abuse exactly the kind of access delete_stairs gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and IFC Bonsai MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for delete_stairs:
{
"version": "1",
"default": "deny",
"hide": [
"delete_stairs"
]
}delete_stairs disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.
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delete_stairs. It is categorised as a Destructive tool in the IFC Bonsai MCP MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the IFC Bonsai MCP server in PolicyLayer and add a rule for delete_stairs: 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 IFC Bonsai MCP. Nothing to install.
delete_stairs 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 delete_stairs 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 delete_stairs. 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.
delete_stairs is provided by the IFC Bonsai MCP server (show2instruct/ifc-bonsai-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 52 IFC Bonsai MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
52 IFC Bonsai MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.