add_wires · Kicad MCP: Risk & Policy

WHAT IT DOES

What add_wires does on Kicad

AI agents use add_wires 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_wires needs a policy

This tool creates new wire connections in a KiCad schematic, which is a reversible modification to the design. It does not execute external code, delete data, or move money. The impact is limited to the electronic design file itself, making it Write severity rather than Execute. Severity is medium because incorrect wiring could alter circuit functionality, but the change is non-destructive and can be undone.

From the tool's definition Tool name 'add_wires' and description 'Add multiple wires at once' indicate creation of schematic elements.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_wires Rate-limited

add_wires 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_wires": {
      "limits": [
        {
          "counter": "add_wires_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_wires

What does the add_wires tool do? +

Add multiple wires at once. Each wire dict has keys: x1, y1, x2, y2. 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_wires? +

Register the Kicad MCP server in PolicyLayer and add a rule for add_wires: 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_wires? +

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

Can I rate-limit add_wires? +

Yes. Add a rate_limit block to the add_wires 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_wires completely? +

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

add_wires 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.