override_props · React Devtools MCP: Risk & Policy

WHAT IT DOES

What override_props does on React Devtools

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

WHY IT NEEDS A POLICY

Why override_props needs a policy

This tool modifies the runtime state of a React component by overriding its props. This is a Write operation as it changes data/state in the running application. Severity is high because an AI agent could use this to alter UI behavior, inject malicious values, or cause application malfunctions across any component in the React tree.

From the tool's definition Override a prop value on a component

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

override_props Rate-limited

override_props 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": {
    "override_props": {
      "limits": [
        {
          "counter": "override_props_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 React Devtools, so you can run agents against it safely.

FAQ

Questions about override_props

What does the override_props tool do? +

Override a prop value on a component. It is categorised as a Write tool in the React Devtools MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on override_props? +

Register the React Devtools MCP server in PolicyLayer and add a rule for override_props: 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 React Devtools. Nothing to install.

What risk level is override_props? +

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

Can I rate-limit override_props? +

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

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

override_props is provided by the React Devtools MCP server (skylarbarrera/react-devtools-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.