Import a design.md (design system specification) into the document. Accepts raw markdown or autoExtract=true to generate from existing document content. The design.md guides AI design generation with consistent colors, typography, and component styles.
AI agents use set_design_md to create or update resources in Pen — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Pen environment.
This tool creates or modifies document state by importing/setting design specifications. It does not delete data, execute external code, or move funds. While it shapes how the AI generates designs, the underlying action is a write operation that updates the design configuration of the document.
From the tool's definition Tool description states 'Import a design.md...into the document' and 'Accepts raw markdown', indicating it modifies document content. The action is reversible (can be replaced or removed), not destructive.
Attacks that exploit this kind of access
Import a design.md (design system specification) into the document. Accepts raw markdown or autoExtract=true to generate from existing document content. The design.md guides AI design generation with consistent colors, typography, and component styles. It is categorised as a Write tool in the Pen MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Pen MCP server in PolicyLayer and add a rule for set_design_md: 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 Pen. Nothing to install.
set_design_md 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 set_design_md 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 set_design_md. 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.
set_design_md is provided by the Pen MCP server (@zseven-w/pen-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →