wait_for_url · Visual Annotation MCP: Risk & Policy

WHAT IT DOES

What wait_for_url does on Visual Annotation MCP

AI agents invoke wait_for_url to trigger actions in Visual Annotation MCP. 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_url needs a policy

This is an Execute category tool because it triggers/controls browser operations and external state monitoring (URL polling), whose effects depend on the URL fragment argument provided. While not immediately destructive or data-modifying, it executes a conditional wait operation that blocks execution and affects downstream actions.

From the tool's definition Tool performs 'wait until current URL contains' - a blocking operation that polls/monitors browser state and controls flow execution timing. It's a synchronous control operation that can affect program execution order and responsiveness.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

wait_for_url Rate-limited

wait_for_url 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_url": {
      "limits": [
        {
          "counter": "wait_for_url_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 Visual Annotation MCP, so you can run agents against it safely.

FAQ

Questions about wait_for_url

What does the wait_for_url tool do? +

Wait until current URL contains the given fragment (useful between flow steps). It is categorised as a Execute tool in the Visual Annotation MCP 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_url? +

Register the Visual Annotation MCP server in PolicyLayer and add a rule for wait_for_url: 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 Visual Annotation MCP. Nothing to install.

What risk level is wait_for_url? +

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

Can I rate-limit wait_for_url? +

Yes. Add a rate_limit block to the wait_for_url 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_url completely? +

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

wait_for_url is provided by the Visual Annotation MCP server (mstocker1/visual_annotation_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.