AI agents invoke nanokvm_reset_hid to trigger actions in NanoKVM MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.
Resetting HID devices triggers an external hardware operation on the NanoKVM device that reinitializes keyboard/mouse emulation. This is an Execute-level action as it causes a real-world hardware state change. Misuse could disrupt active keyboard/mouse input sessions on the remotely controlled machine, but effects are generally recoverable (devices reinitialize), keeping severity at medium.
From the tool's definition Reset the HID (keyboard/mouse) devices
Documented attack patterns abuse exactly the kind of access nanokvm_reset_hid gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and NanoKVM MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for nanokvm_reset_hid:
{
"version": "1",
"default": "deny",
"tools": {
"nanokvm_reset_hid": {
"limits": [
{
"counter": "nanokvm_reset_hid_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}nanokvm_reset_hid stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Reset the HID (keyboard/mouse) devices. It is categorised as a Execute tool in the NanoKVM MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the NanoKVM MCP Server MCP server in PolicyLayer and add a rule for nanokvm_reset_hid: 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 NanoKVM MCP Server. Nothing to install.
nanokvm_reset_hid is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the nanokvm_reset_hid 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 nanokvm_reset_hid. 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.
nanokvm_reset_hid is provided by the NanoKVM MCP Server MCP server (scgreenhalgh/nanokvm-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from NanoKVM MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
19 NanoKVM MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.