apply_design_context · Stitch MCP Server MCP: Risk & Policy

WHAT IT DOES

What apply_design_context does on Stitch MCP Server

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

WHY IT NEEDS A POLICY

Why apply_design_context needs a policy

This tool creates or modifies design screens within the Stitch workspace, which is a Write operation. It does not delete data (ruling out Destructive), execute arbitrary code (ruling out Execute), or move money (ruling out Financial). The severity is medium because generating unintended screens could pollute a design system but can be reverted.

From the tool's definition Tool description states 'Generates a new screen' which creates new design artifacts in the project workspace. The word 'Generates' indicates creation of reversible design content.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

apply_design_context Rate-limited

apply_design_context 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": {
    "apply_design_context": {
      "limits": [
        {
          "counter": "apply_design_context_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 Stitch MCP Server, so you can run agents against it safely.

FAQ

Questions about apply_design_context

What does the apply_design_context tool do? +

Generates a new screen using a previously extracted design context for visual consistency. It is categorised as a Write tool in the Stitch MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on apply_design_context? +

Register the Stitch MCP Server MCP server in PolicyLayer and add a rule for apply_design_context: 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 Stitch MCP Server. Nothing to install.

What risk level is apply_design_context? +

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

Can I rate-limit apply_design_context? +

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

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

apply_design_context is provided by the Stitch MCP Server MCP server (oogleyskr/stitch-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.