create-watermark · Quickchart MCP: Risk & Policy

WHAT IT DOES

What create-watermark does on Quickchart

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

WHY IT NEEDS A POLICY

Why create-watermark needs a policy

This tool creates or modifies image files by adding watermarks/logos. It is a Write operation because it produces new or modified data (watermarked images) without irreversible deletion. The severity is low because watermarking is a non-destructive image transformation with minimal blast radius—misuse would result in unwanted watermarks on images, which can be corrected by reprocessing or using the original.

From the tool's definition Tool description states 'Add watermarks/logos to images' and 'save watermarked image to file', indicating creation and modification of image data. The action is reversible—a watermarked image can be regenerated or the original reused.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create-watermark Rate-limited

create-watermark 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": {
    "create-watermark": {
      "limits": [
        {
          "counter": "create-watermark_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 Quickchart, so you can run agents against it safely.

FAQ

Questions about create-watermark

What does the create-watermark tool do? +

Add watermarks/logos to images using QuickChart - get watermarked image URL or save watermarked image to file. It is categorised as a Write tool in the Quickchart MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create-watermark? +

Register the Quickchart MCP server in PolicyLayer and add a rule for create-watermark: 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 Quickchart. Nothing to install.

What risk level is create-watermark? +

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

Can I rate-limit create-watermark? +

Yes. Add a rate_limit block to the create-watermark 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 create-watermark completely? +

Set action: deny in the PolicyLayer policy for create-watermark. 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 create-watermark? +

create-watermark is provided by the Quickchart MCP server (takanarishimbo/quickchart-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.