env_list

List environment variables (secrets are masked).

SERVERYaver SOURCEyaver-cli

Low RISK CLASS

Category Read

Parameters 10 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-kivanccakmak-yaver/env-list.md

WHAT IT DOES

What env_list does on Yaver

AI agents call env_list to retrieve information from Yaver without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Parameter	Type	Required	Description
`filter`	string	—	Filter by name (case-insensitive)

Parameters from the server's own tool schema.

RISK

Why env_list is rated Low

This tool retrieves and displays environment variable information without modifying, deleting, or executing code. The explicit masking of secrets further confirms it is designed for safe inspection only. The blast radius is minimal—an agent can only view configuration metadata, not alter system state or access sensitive values.

From the tool's definition Tool name is 'env_list' and description states 'List environment variables (secrets are masked).' The verb 'List' and the masking of secrets indicate a read-only operation with no side effects.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs env_list safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Yaver, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For env_list, this is the rule to start with:

env_list Allowed

env_list is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "env_list": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Yaver, apply this rule, and every env_list call is checked against it from then on.

FAQ

Questions about env_list

What does the env_list tool do? +

List environment variables (secrets are masked). It is categorised as a Read tool in the Yaver MCP Server, which means it retrieves data without modifying state.

What parameters does env_list accept? +

env_list accepts 1 parameter: filter. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on env_list? +

Register the Yaver MCP server in PolicyLayer and add a rule for env_list: 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 Yaver. Nothing to install.

What risk level is env_list? +

env_list is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit env_list? +

Yes. Add a rate_limit block to the env_list 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.

How do I block env_list completely? +

Set action: deny in the PolicyLayer policy for env_list. 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.

What MCP server provides env_list? +

env_list is provided by the Yaver MCP server (yaver-cli). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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