AI agents call getEnv to retrieve information from MCPX MCP Gateway without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves environment variable values without side effects, fitting the Read category. However, severity is elevated to medium rather than low because environment variables may contain sensitive credentials (API keys, database passwords, tokens), and an AI agent with unrestricted access could exfiltrate this data. The MCPX gateway's mention of tool-level access controls suggests this risk is recognized.
From the tool's definition Tool name 'getEnv' and description 'Returns the value of a specified environment variable' indicate read-only retrieval of data with no modification or execution of code.
Documented attack patterns abuse exactly the kind of access getEnv gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCPX MCP Gateway, and nothing reaches the server without passing your rules. This is the rule we recommend for getEnv:
{
"version": "1",
"default": "deny",
"tools": {
"getEnv": {}
}
}getEnv is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Returns the value of a specified environment variable. It is categorised as a Read tool in the MCPX MCP Gateway MCP Server, which means it retrieves data without modifying state.
Register the MCPX MCP Gateway MCP server in PolicyLayer and add a rule for getEnv: 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 MCPX MCP Gateway. Nothing to install.
getEnv 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 getEnv 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 getEnv. 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.
getEnv is provided by the MCPX MCP Gateway MCP server (thelunarcompany/lunar). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 14 MCPX MCP Gateway tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
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14 MCPX MCP Gateway tools catalogued and risk-classified — across an index of 42,500+ MCP servers.