Lists all frames (including iframes) in the current page as a tree. Shows frame index, name, and URL. Use select_frame to switch execution context to a specific frame.
AI agents call list_frames to retrieve information from JS Reverse MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves structural information about the DOM frame hierarchy without side effects. It does not execute code, modify data, delete resources, or trigger external operations. The capability to inspect frames is a fundamental read-only debugging operation in browser automation contexts.
From the tool's definition Tool 'lists all frames' and 'shows frame index, name, and URL' — describes information retrieval with no modification or execution.
Attacks that exploit this kind of access
Lists all frames (including iframes) in the current page as a tree. Shows frame index, name, and URL. Use select_frame to switch execution context to a specific frame. It is categorised as a Read tool in the JS Reverse MCP MCP Server, which means it retrieves data without modifying state.
Register the JS Reverse MCP server in PolicyLayer and add a rule for list_frames: 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 JS Reverse MCP. Nothing to install.
list_frames 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 list_frames 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 list_frames. 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.
list_frames is provided by the JS Reverse MCP server (noone-hub/jsreverser-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →