modify_hierarchical_label · Kicad MCP: Risk & Policy

WHAT IT DOES

What modify_hierarchical_label does on Kicad

AI agents use modify_hierarchical_label 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 modify_hierarchical_label needs a policy

This tool modifies hierarchical labels in KiCad schematics, which are design elements that can be changed or reverted. Modification of schematic labels is a write operation with medium severity—incorrect label changes could cause design errors or require rework, but changes are not irreversible and do not destroy data.

From the tool's definition Tool name 'modify_hierarchical_label' indicates modification of design elements in KiCad schematics. Sibling tools like 'add_hierarchical_label' and 'add_global_label' are write operations that create/modify schematic annotations.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

modify_hierarchical_label Rate-limited

modify_hierarchical_label 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": {
    "modify_hierarchical_label": {
      "limits": [
        {
          "counter": "modify_hierarchical_label_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 modify_hierarchical_label

What does the modify_hierarchical_label tool do? +

modify_hierarchical_label. 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 modify_hierarchical_label? +

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

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

Can I rate-limit modify_hierarchical_label? +

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

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

modify_hierarchical_label 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.