Assert element exists and is visible. Returns success/fail (no throw).
AI agents call assert_element_visible to retrieve information from MCP Camoufox without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool only checks whether a DOM element is visible on the page and returns a boolean result. It reads browser state without modifying anything, executing code, or causing side effects.
From the tool's definition Assert element exists and is visible. Returns success/fail (no throw).
Documented attack patterns abuse exactly the kind of access assert_element_visible gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Camoufox, and nothing reaches the server without passing your rules. This is the rule we recommend for assert_element_visible:
{
"version": "1",
"default": "deny",
"tools": {
"assert_element_visible": {}
}
}assert_element_visible is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Assert element exists and is visible. Returns success/fail (no throw). It is categorised as a Read tool in the MCP Camoufox MCP Server, which means it retrieves data without modifying state.
Register the MCP Camoufox MCP server in PolicyLayer and add a rule for assert_element_visible: 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 MCP Camoufox. Nothing to install.
assert_element_visible is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the assert_element_visible 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.
Set action: deny in the PolicyLayer policy for assert_element_visible. 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.
assert_element_visible is provided by the MCP Camoufox MCP server (robithyusuf/mcp-camoufox). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from MCP Camoufox, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
102 MCP Camoufox tools catalogued and risk-classified — across an index of 43,000+ MCP servers.