delete_symbol

THE RISK

Critical Risk

Why delete_symbol needs a policy

This tool performs irreversible deletion of symbol definitions from KiCAD library files. Once removed, the symbol is gone from the library and any designs referencing it may break. This is a destructive operation that modifies the persistent library state and cannot be easily reversed during normal operation, justifying the Destructive category and high severity due to potential data loss and project impact.

From the tool's definition 'Remove a symbol from a .kicad_sym library file' — the tool irreversibly deletes data from a library, which cannot be undone without restoration from backup.

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

POLICY

How to control delete_symbol

PolicyLayer is an MCP gateway — it sits between your AI agents and KiCAD-MCP-Server, and nothing reaches the server without passing your rules. This is the rule we recommend for delete_symbol:

policy.json

{
  "version": "1",
  "default": "deny",
  "hide": [
    "delete_symbol"
  ]
}

delete_symbol disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.

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

RESTRICT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More KiCAD-MCP-Server tools

Destructive delete_component Remove a component from the PCB by its reference designator. Destructive delete_schematic_component Remove a placed symbol from a KiCAD schematic (.kicad_sch). This removes the symbol insta Destructive delete_schematic_net_label Remove a net label from the schematic. Destructive delete_schematic_wire Remove a wire from the schematic by start and end coordinates. Destructive delete_trace Delete traces from the PCB. Can delete by UUID, position, or bulk-delete all traces on a n Destructive remove_schematic_component_property Remove a single custom property from a placed schematic symbol. Built-in fields (Referenc Execute autoroute Run Freerouting autorouter on the current PCB. Exports to Specctra DSN, runs Freerouting C Execute launch_kicad_ui Launch KiCAD UI, optionally with a project file

All 157 KiCAD-MCP-Server tools →

Destructive tools on other servers

Android Forensics ADB MCP Server create_full_backup 0xarchive web3_revoke_key Frida Game Hacking MCP clear_scan cPanel MCP Server clear_spam_box

Go deeper

Critical-risk tools in KiCAD-MCP-Server → Every critical-risk tool this server exposes, in one view.
All critical-risk MCP tools → Every critical-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Blast radius → How much damage one compromised or confused agent can do — and how to bound it.
Tool call approval → Approval gates on individual tool calls: auto-allow, prompt, or deny.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about delete_symbol

What does the delete_symbol tool do? +

Remove a symbol from a .kicad_sym library file. It is categorised as a Destructive tool in the KiCAD-MCP-Server MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.

How do I enforce a policy on delete_symbol? +

Register the KiCAD-MCP-Server MCP server in PolicyLayer and add a rule for delete_symbol: 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-MCP-Server. Nothing to install.

What risk level is delete_symbol? +

delete_symbol is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit delete_symbol? +

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

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

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

Enforce policy on every KiCAD-MCP-Server tool call.

Start from KiCAD-MCP-Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →