preview_browser · SVG Canvas MCP: Risk & Policy

WHAT IT DOES

What preview_browser does on SVG Canvas MCP

AI agents invoke preview_browser to trigger actions in SVG Canvas MCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why preview_browser needs a policy

This tool launches or interacts with a browser to preview the canvas, leveraging Playwright. Since it executes browser automation (an external operation), it falls under Execute. The blast radius is medium as it opens a browser session but does not modify or delete data.

From the tool's definition 브라우저에서 미리봅니다 (Playwright MCP 연동) — triggers an external browser action via Playwright integration

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

preview_browser Rate-limited

preview_browser stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "preview_browser": {
      "limits": [
        {
          "counter": "preview_browser_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches SVG Canvas MCP, so you can run agents against it safely.

FAQ

Questions about preview_browser

What does the preview_browser tool do? +

현재 캔버스를 브라우저에서 미리봅니다. (Playwright MCP 연동). It is categorised as a Execute tool in the SVG Canvas MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on preview_browser? +

Register the SVG Canvas MCP server in PolicyLayer and add a rule for preview_browser: 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 SVG Canvas MCP. Nothing to install.

What risk level is preview_browser? +

preview_browser is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit preview_browser? +

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

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

preview_browser is provided by the SVG Canvas MCP server (kim62210/svg-canvas-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.