AI agents call delete_firewall_rule to permanently remove resources in OPNSense MCP Server — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
Deleting firewall rules is a destructive action that cannot be undone without manual restoration. This directly falls under the Destructive category. The severity is high because misconfiguration or accidental deletion of critical firewall rules could expose a network to unauthorized access or traffic, causing significant security impacts.
From the tool's definition Tool name 'delete_firewall_rule' and description 'Delete a firewall rule' explicitly perform an irreversible deletion operation on firewall configuration.
Documented attack patterns abuse exactly the kind of access delete_firewall_rule gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and OPNSense MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for delete_firewall_rule:
{
"version": "1",
"default": "deny",
"hide": [
"delete_firewall_rule"
]
}delete_firewall_rule disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.
Free to start. No card required.
Delete a firewall rule. It is categorised as a Destructive tool in the OPNSense MCP Server MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the OPNSense MCP Server MCP server in PolicyLayer and add a rule for delete_firewall_rule: 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 OPNSense MCP Server. Nothing to install.
delete_firewall_rule 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_firewall_rule 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_firewall_rule. 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_firewall_rule is provided by the OPNSense MCP Server MCP server (vespo92/opnsensemcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 196 OPNSense MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
196 OPNSense MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.