select_option · Nextjs Agent MCP: Risk & Policy

WHAT IT DOES

What select_option does on Nextjs Agent

AI agents invoke select_option to trigger actions in Nextjs Agent. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why select_option needs a policy

This tool performs an interactive browser action (opening a dropdown and selecting an option) via the in-page DOM bridge, which constitutes executing a UI interaction with potential side effects depending on what the option selection triggers in the app.

From the tool's definition 'Open a composed dropdown/combobox and select the option matching' — triggers a real DOM-based browser interaction that drives a running Next.js app

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

select_option Rate-limited

select_option stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "select_option": {
      "limits": [
        {
          "counter": "select_option_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Nextjs Agent, so you can run agents against it safely.

FAQ

Questions about select_option

What does the select_option tool do? +

Open a composed dropdown/combobox and select the option matching. It is categorised as a Execute tool in the Nextjs Agent MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on select_option? +

Register the Nextjs Agent MCP server in PolicyLayer and add a rule for select_option: 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 Nextjs Agent. Nothing to install.

What risk level is select_option? +

select_option is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit select_option? +

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

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

select_option is provided by the Nextjs Agent MCP server (zohaib3249/nextjs-agent-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.