Add a text label to a PCB layer (e.g. silkscreen, fab, courtyard).
AI agents use add_board_text to create or update resources in KiCAD-MCP-Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your KiCAD-MCP-Server environment.
This tool creates new text elements (silkscreen labels, fab notes, courtyard markings, etc.) on a PCB. While it modifies the design, the addition is reversible through standard undo/delete operations. It does not execute arbitrary code, delete data permanently, or cause financial transactions.
From the tool's definition Tool description states 'Add a text label to a PCB layer', indicating creation of new text objects on a PCB design. The verb 'Add' and the action of placing text labels represent reversible modifications to the PCB design.
Documented attack patterns abuse exactly the kind of access add_board_text gives an agent:
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 add_board_text:
{
"version": "1",
"default": "deny",
"tools": {
"add_board_text": {
"limits": [
{
"counter": "add_board_text_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
} add_board_text 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.
Free to start. No card required.
Add a text label to a PCB layer (e.g. silkscreen, fab, courtyard). It is categorised as a Write tool in the KiCAD-MCP-Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the KiCAD-MCP-Server MCP server in PolicyLayer and add a rule for add_board_text: 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.
add_board_text is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the add_board_text 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.
Set action: deny in the PolicyLayer policy for add_board_text. 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.
add_board_text 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.
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.
Free to start. No card required.
157 KiCAD-MCP-Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.