AI agents invoke drawing_open to trigger actions in AutoCAD MCP Pro. 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.
Opening a drawing file triggers an external operation in AutoCAD (via COM), loading and activating a file in the application. This goes beyond a read operation as it changes the application state and initiates file I/O through AutoCAD's COM interface. It is not purely destructive or a write, but it executes an external operation with side effects on the running AutoCAD instance.
From the tool's definition Open an existing DWG or DXF drawing file
Documented attack patterns abuse exactly the kind of access drawing_open 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_open:
{
"version": "1",
"default": "deny",
"tools": {
"drawing_open": {
"limits": [
{
"counter": "drawing_open_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}drawing_open 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.
Open an existing DWG or DXF drawing file. It is categorised as a Execute tool in the AutoCAD MCP Pro MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the AutoCAD MCP Pro MCP server in PolicyLayer and add a rule for drawing_open: 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_open 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 drawing_open 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_open. 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_open 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.