AI agents call browser_start_record_network to retrieve information from Byob without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool starts capturing network traffic (requests, responses, bodies, timings) from the browser session. It is primarily a Read/monitoring operation — it observes and records data without modifying it. However, it has medium severity because it can capture sensitive data including cookies, auth tokens, POST bodies, and credentials from existing logged-in sessions.
From the tool's definition Begin recording HTTP/HTTPS requests, responses, bodies, timings
Attacks that exploit this kind of access
Begin recording HTTP/HTTPS requests, responses, bodies, timings, and. It is categorised as a Read tool in the Byob MCP Server, which means it retrieves data without modifying state.
Register the Byob MCP server in PolicyLayer and add a rule for browser_start_record_network: 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 Byob. Nothing to install.
browser_start_record_network 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 browser_start_record_network 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 browser_start_record_network. 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.
browser_start_record_network is provided by the Byob MCP server (wxtsky/byob). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.