set_corner_radius · MCP Figma MCP: Risk & Policy

WHAT IT DOES

What set_corner_radius does on MCP Figma

AI agents use set_corner_radius to create or update resources in MCP Figma — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your MCP Figma environment.

WHY IT NEEDS A POLICY

Why set_corner_radius needs a policy

This tool creates or modifies design properties reversibly without deleting data or triggering irreversible actions. It fits the Write category—it changes a design element's appearance but the change can be easily undone or modified. Severity is low because misuse only affects visual styling of a single design element with no data loss, financial impact, or external system effects.

From the tool's definition Tool modifies a visual property (corner radius) of a Figma design node. The description states it "Set[s] the corner radius" which is a reversible design modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_corner_radius Rate-limited

set_corner_radius 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": {
    "set_corner_radius": {
      "limits": [
        {
          "counter": "set_corner_radius_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 MCP Figma, so you can run agents against it safely.

FAQ

Questions about set_corner_radius

What does the set_corner_radius tool do? +

Set the corner radius of a node in Figma. It is categorised as a Write tool in the MCP Figma MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_corner_radius? +

Register the MCP Figma MCP server in PolicyLayer and add a rule for set_corner_radius: 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 MCP Figma. Nothing to install.

What risk level is set_corner_radius? +

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

Can I rate-limit set_corner_radius? +

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

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

set_corner_radius is provided by the MCP Figma MCP server (yelowflash09/figma_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.