AI agents call get_sandbox_url to retrieve information from E2b without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves metadata (a URL) associated with an existing sandbox. It has no side effects, does not execute code or commands, does not modify data, and does not delete resources. It is purely informational, similar to a 'get' or 'fetch' operation.
From the tool's definition Tool name 'get_sandbox_url' and description 'Get the URL for a sandbox on a specific port' indicate retrieval of URL information without data modification or execution.
Attacks that exploit this kind of access
Get the URL for a sandbox on a specific port. It is categorised as a Read tool in the E2b MCP Server, which means it retrieves data without modifying state.
Register the E2b MCP server in PolicyLayer and add a rule for get_sandbox_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 E2b. Nothing to install.
get_sandbox_url 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 get_sandbox_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.
Set action: deny in the PolicyLayer policy for get_sandbox_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.
get_sandbox_url is provided by the E2b MCP server (yukkit/e2b-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
get_sandbox_url is one line of E2b's registry record.
The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.
Teams ship this data inside their own products. See what a licence covers →