AI agents use drawing_undo to create or update resources in AutoCAD MCP Pro — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your AutoCAD MCP Pro environment.
This tool modifies drawing state (reverts it to a previous version), making it a Write operation rather than Read. It is not Destructive because undo operations are inherently reversible—the undone changes can be redone, and no data is permanently lost. The severity is medium because excessive or malicious undo calls could disrupt a legitimate workflow or CAD process, but the operation itself is not data-destructive.
From the tool's definition Tool name 'drawing_undo' and description 'Undo the last drawing operation' indicates reversal of a prior modification to drawing state.
Documented attack patterns abuse exactly the kind of access drawing_undo gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and AutoCAD MCP Pro, and nothing reaches the server without passing your rules. This is the rule we recommend for drawing_undo:
{
"version": "1",
"default": "deny",
"tools": {
"drawing_undo": {
"limits": [
{
"counter": "drawing_undo_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}drawing_undo 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.
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Undo the last drawing operation. It is categorised as a Write tool in the AutoCAD MCP Pro MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the AutoCAD MCP Pro MCP server in PolicyLayer and add a rule for drawing_undo: 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 AutoCAD MCP Pro. Nothing to install.
drawing_undo 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 drawing_undo 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 drawing_undo. 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.
drawing_undo is provided by the AutoCAD MCP Pro MCP server (u-c4n/autocad-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from AutoCAD MCP Pro, 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.
108 AutoCAD MCP Pro tools catalogued and risk-classified — across an index of 43,000+ MCP servers.