wait_for_dom_stable · Selenium MCP: Risk & Policy

WHAT IT DOES

What wait_for_dom_stable does on Selenium

AI agents invoke wait_for_dom_stable to trigger actions in Selenium. 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 wait_for_dom_stable needs a policy

While the tool itself appears to be a waiting/synchronization utility rather than a direct destructive or write operation, it is an Execute category tool because it triggers and controls browser behavior—specifically, it programmatically waits for and reacts to DOM mutations.

From the tool's definition Tool name 'wait_for_dom_stable' and description 'Wait until the DOM stops mutating (smart wait for AJAX content)' indicate this triggers browser operations that observe and monitor DOM state.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

wait_for_dom_stable Rate-limited

wait_for_dom_stable 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": {
    "wait_for_dom_stable": {
      "limits": [
        {
          "counter": "wait_for_dom_stable_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 Selenium, so you can run agents against it safely.

FAQ

Questions about wait_for_dom_stable

What does the wait_for_dom_stable tool do? +

Wait until the DOM stops mutating (smart wait for AJAX content). It is categorised as a Execute tool in the Selenium MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on wait_for_dom_stable? +

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

What risk level is wait_for_dom_stable? +

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

Can I rate-limit wait_for_dom_stable? +

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

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

wait_for_dom_stable is provided by the Selenium MCP server (scv-consultants/selenium-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.