update_startup_script
AI agents use update_startup_script to create or update resources in Vultr MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Vultr MCP environment.
Startup scripts execute arbitrary code at instance initialization. Modifying them could alter system behavior, install malicious software, or compromise instance security. However, since updates are reversible (old versions can be restored), this is Write rather than Execute or Destructive. High severity due to the wide-ranging implications of startup script changes across potentially many instances. Confidence is 0.
From the tool's definition Tool name 'update_startup_script' indicates modification of startup scripts, which are configuration files that execute when instances boot. The verb 'update' confirms reversible modification rather than deletion.
Documented attack patterns abuse exactly the kind of access update_startup_script gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Vultr MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for update_startup_script:
{
"version": "1",
"default": "deny",
"tools": {
"update_startup_script": {
"limits": [
{
"counter": "update_startup_script_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}update_startup_script stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
update_startup_script. It is categorised as a Write tool in the Vultr MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Vultr MCP server in PolicyLayer and add a rule for update_startup_script: 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 Vultr MCP. Nothing to install.
update_startup_script is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the update_startup_script 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 update_startup_script. 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.
update_startup_script is provided by the Vultr MCP server (rsp2k/mcp-vultr). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Vultr MCP, 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.
284 Vultr MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.