add_sheet_pin · Kicad MCP: Risk & Policy

WHAT IT DOES

What add_sheet_pin does on Kicad

AI agents use add_sheet_pin to create or update resources in Kicad — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Kicad environment.

WHY IT NEEDS A POLICY

Why add_sheet_pin needs a policy

This tool creates new sheet pins in KiCad hierarchical schematics, which are structural additions that modify the schematic design. Sheet pins define connections between hierarchical sheets and are reversible changes (can be deleted). While the description is empty, context from sibling tools and naming convention clearly indicate a Write operation.

From the tool's definition Tool name 'add_sheet_pin' indicates a creation/addition operation on KiCad schematics. Sibling tools like 'add_copper_zone', 'add_global_label', 'add_hierarchical_sheet' all perform reversible modifications to design files.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_sheet_pin Rate-limited

add_sheet_pin 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "add_sheet_pin": {
      "limits": [
        {
          "counter": "add_sheet_pin_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Kicad, so you can run agents against it safely.

FAQ

Questions about add_sheet_pin

What does the add_sheet_pin tool do? +

add_sheet_pin. It is categorised as a Write tool in the Kicad MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_sheet_pin? +

Register the Kicad MCP server in PolicyLayer and add a rule for add_sheet_pin: 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 Kicad. Nothing to install.

What risk level is add_sheet_pin? +

add_sheet_pin is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit add_sheet_pin? +

Yes. Add a rate_limit block to the add_sheet_pin 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 add_sheet_pin completely? +

Set action: deny in the PolicyLayer policy for add_sheet_pin. 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 add_sheet_pin? +

add_sheet_pin is provided by the Kicad MCP server (productofamerica/mcp-server-kicad). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.