retheme_artifact · Web Gui MCP: Risk & Policy

WHAT IT DOES

What retheme_artifact does on Web Gui

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

WHY IT NEEDS A POLICY

Why retheme_artifact needs a policy

Based on the name, this tool likely modifies (re-themes) an existing artifact, which is a reversible write operation. However, the empty description significantly lowers confidence. The server stores artifacts in memory, so the blast radius is limited to in-memory state.

From the tool's definition Tool name 'retheme_artifact' and server context suggest modifying an artifact's theme/styling; description is empty and uninformative.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

retheme_artifact Rate-limited

retheme_artifact 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": {
    "retheme_artifact": {
      "limits": [
        {
          "counter": "retheme_artifact_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 Web Gui, so you can run agents against it safely.

FAQ

Questions about retheme_artifact

What does the retheme_artifact tool do? +

retheme_artifact. It is categorised as a Write tool in the Web Gui MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on retheme_artifact? +

Register the Web Gui MCP server in PolicyLayer and add a rule for retheme_artifact: 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 Web Gui. Nothing to install.

What risk level is retheme_artifact? +

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

Can I rate-limit retheme_artifact? +

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

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

retheme_artifact is provided by the Web Gui MCP server (thehzuo/gui-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.