export_png · SVG Canvas MCP: Risk & Policy

WHAT IT DOES

What export_png does on SVG Canvas MCP

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

WHY IT NEEDS A POLICY

Why export_png needs a policy

This tool creates and writes output files (PNG exports) to storage, which is a reversible write operation. It does not execute arbitrary code, delete data, or move money. The severity is medium rather than low because uncontrolled file export could fill storage, overwrite existing files, or exfiltrate sensitive design data if an agent misuses it.

From the tool's definition Tool name is 'export_png' and description indicates it exports/saves files. The description states 'PNG 파일로 내보냅니다' (exports to PNG file), which is a write operation that creates a new file artifact.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

export_png Rate-limited

export_png 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": {
    "export_png": {
      "limits": [
        {
          "counter": "export_png_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 SVG Canvas MCP, so you can run agents against it safely.

FAQ

Questions about export_png

What does the export_png tool do? +

PNG 파일로 내보냅니다. (참고: 현재는 SVG를 저장하고 별도 변환 도구 사용 권장). It is categorised as a Write tool in the SVG Canvas MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on export_png? +

Register the SVG Canvas MCP server in PolicyLayer and add a rule for export_png: 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 export_png? +

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

Can I rate-limit export_png? +

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

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

export_png 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.