block_list

THE RISK

Low Risk

Why block_list needs a policy

This tool retrieves and enumerates existing block definitions without creating, modifying, deleting, or executing any operations. It is a passive information-gathering operation with no blast radius if misused by an AI agent. The data returned is read-only metadata about the drawing structure.

From the tool's definition Tool name 'block_list' and description 'List all block definitions in the drawing' indicate a query/retrieval operation with no modification or side effects. Returns metadata: name, origin, attribute count, entity count.

Documented attack patterns abuse exactly the kind of access block_list gives an agent:

POLICY

How to control block_list

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 block_list:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "block_list": {}
  }
}

block_list is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register AutoCAD MCP Pro — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More AutoCAD MCP Pro tools

Destructive construction_clear Delete every entity on the CONSTRUCTION layer. Idempotent. Destructive drawing_purge Purge all unused objects (layers, blocks, linetypes, styles) from the drawing. Destructive entity_delete Permanently delete an entity by its handle. Destructive entity_delete_many Delete multiple entities in one call. Returns count of deleted entities. Destructive layer_delete layer_delete Destructive block_explode block_explode Execute drawing_audit Run an integrity audit on the drawing to detect and fix errors. Execute system_run_command system_run_command

All 108 AutoCAD MCP Pro tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about block_list

What does the block_list tool do? +

List all block definitions in the drawing (name, origin, attribute count, entity count). It is categorised as a Read tool in the AutoCAD MCP Pro MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on block_list? +

Register the AutoCAD MCP Pro MCP server in PolicyLayer and add a rule for block_list: 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.

What risk level is block_list? +

block_list is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit block_list? +

Yes. Add a rate_limit block to the block_list 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.

How do I block block_list completely? +

Set action: deny in the PolicyLayer policy for block_list. 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.

What MCP server provides block_list? +

block_list 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.

Enforce policy on every AutoCAD MCP Pro tool call.

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.

CHECK YOUR STACK →