AI agents call find_devices_on_vlan to retrieve information from OPNSense MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool performs a read-only query to enumerate devices on a specific VLAN. It retrieves network discovery data with no side effects, no destructive capability, no code execution, and no financial impact. The low severity reflects that misuse would at worst expose non-sensitive network topology information in most configurations.
From the tool's definition Tool name 'find_devices_on_vlan' and description 'Find devices on specific VLAN' indicate a query/discovery operation that retrieves information about network devices without modifying, deleting, or executing external operations.
Documented attack patterns abuse exactly the kind of access find_devices_on_vlan 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 find_devices_on_vlan:
{
"version": "1",
"default": "deny",
"tools": {
"find_devices_on_vlan": {}
}
}find_devices_on_vlan is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Find devices on specific VLAN. It is categorised as a Read tool in the OPNSense MCP Server MCP Server, which means it retrieves data without modifying state.
Register the OPNSense MCP Server MCP server in PolicyLayer and add a rule for find_devices_on_vlan: 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.
find_devices_on_vlan is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the find_devices_on_vlan 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 find_devices_on_vlan. 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.
find_devices_on_vlan 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.