generate_variants · Musea MCP: Risk & Policy

WHAT IT DOES

What generate_variants does on Musea

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

WHY IT NEEDS A POLICY

Why generate_variants needs a policy

The tool generates design variants for Vue components, which creates new data artifacts (variant definitions, configurations, or documentation outputs) in a reversible manner. This is a Write operation—it produces outputs that can be modified or deleted, not a Read operation (which would only query existing data) nor an Execute operation (which would run arbitrary code with side effects).

From the tool's definition Tool name 'generate_variants' combined with context showing it works with Vue.js design systems for 'variant generation' and the description 'Analyze a Vue component' indicates it creates or generates new variant outputs (Write operation) rather than merely…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

generate_variants Rate-limited

generate_variants 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": {
    "generate_variants": {
      "limits": [
        {
          "counter": "generate_variants_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 Musea, so you can run agents against it safely.

FAQ

Questions about generate_variants

What does the generate_variants tool do? +

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

How do I enforce a policy on generate_variants? +

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

What risk level is generate_variants? +

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

Can I rate-limit generate_variants? +

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

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

generate_variants is provided by the Musea MCP server (@vizejs/musea-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.