cloak_fill_form · CloakBrowser MCP Server MCP: Risk & Policy

WHAT IT DOES

What cloak_fill_form does on CloakBrowser MCP Server

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

WHY IT NEEDS A POLICY

Why cloak_fill_form needs a policy

The tool modifies form state by populating fields, which is a reversible write operation. However, severity is elevated to 'high' because: (1) it operates within a stealth browser designed to bypass bot detection, increasing misuse risk; (2) form filling can be chained with submission (via cloak_click) to commit unauthorized transactions, account takeovers, or fraudulent submissions; (3) the blast radius depends on…

From the tool's definition Tool name 'cloak_fill_form' and description 'Fill multiple form fields at once' indicate modification of form data. Sibling tools like 'cloak_click', 'cloak_drag', 'cloak_evaluate' confirm this is a browser automation server for web interaction.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

cloak_fill_form Rate-limited

cloak_fill_form 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": {
    "cloak_fill_form": {
      "limits": [
        {
          "counter": "cloak_fill_form_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 CloakBrowser MCP Server, so you can run agents against it safely.

FAQ

Questions about cloak_fill_form

What does the cloak_fill_form tool do? +

Fill multiple form fields at once. It is categorised as a Write tool in the CloakBrowser 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 cloak_fill_form? +

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

What risk level is cloak_fill_form? +

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

Can I rate-limit cloak_fill_form? +

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

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

cloak_fill_form is provided by the CloakBrowser MCP Server MCP server (miwoomiwoo/cloakbrowser-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.