# firewall_delete_rule

Delete a firewall rule by UUID

Agent View of the PolicyLayer registry record for `firewall_delete_rule`. HTML page: https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/firewall-delete-rule

## Facts

- Tool: `firewall_delete_rule`
- Server: OPNsense MCP Server (`fakebizprez/opnsense-mcp-server`) — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server.md
- Homepage: https://github.com/fakebizprez/opnsense-mcp-server
- Risk category: Destructive (Critical risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Hidden

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "firewall_delete_rule",
    "arguments": {}
  }
}
```

## Why firewall_delete_rule is rated Critical

Deleting firewall rules is a destructive operation that cannot be undone and directly impacts security posture. An AI agent misusing this tool could remove critical rules protecting the network, causing immediate security exposure. This is more severe than Write (which is reversible) but not Financial.

From the tool's own definition: "Tool name 'firewall_delete_rule' combined with description 'Delete a firewall rule by UUID' explicitly indicates irreversible deletion of firewall configuration data."

## Use case

AI agents call firewall_delete_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.

## Recommended policy (PolicyLayer)

Verdict: **Hidden**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches OPNsense MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "hide": [
    "firewall_delete_rule"
  ]
}
```

## Other tools on OPNsense MCP Server (21)

- `delete_from_alias` — Destructive — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/delete-from-alias.md
- `exec_api_call` — Execute — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/exec-api-call.md
- `install_plugin` — Execute — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/install-plugin.md
- `restart_service` — Execute — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/restart-service.md
- `firewall_get_rules` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/firewall-get-rules.md
- `firewall_toggle_rule` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/firewall-toggle-rule.md
- `get_api_endpoints` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-api-endpoints.md
- `get_dhcp_leases` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-dhcp-leases.md
- `get_firewall_aliases` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-firewall-aliases.md
- `get_firewall_logs` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-firewall-logs.md
- `get_interfaces` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-interfaces.md
- `get_system_health` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-system-health.md
- `get_system_routes` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-system-routes.md
- `get_system_status` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-system-status.md
- `get_vpn_connections` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/get-vpn-connections.md
- `list_plugins` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/list-plugins.md
- `perform_firewall_audit` — Read — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/perform-firewall-audit.md
- `add_to_alias` — Write — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/add-to-alias.md
- `backup_config` — Write — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/backup-config.md
- `configure_opnsense_connection` — Write — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/configure-opnsense-connection.md
- `firewall_add_rule` — Write — https://policylayer.com/tools/fakebizprez-opnsense-mcp-server/firewall-add-rule.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

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Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=fakebizprez-opnsense-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/fakebizprez-opnsense-mcp-server