usergroups_users_list

A read tool on the Slack MCP server.

SERVERSlack SOURCEkarbassi/slack-mcp

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/karbassi-slack-mcp/usergroups-users-list.md

WHAT IT DOES

What usergroups_users_list does on Slack

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

RISK

Why usergroups_users_list is rated Low

This tool appears to list users within user groups, a retrieval operation with no side effects. It retrieves data from Slack's user group management system without modifying, executing, or deleting anything. The blast radius of misuse is low—exposure of user group membership information, which is typically low-sensitivity organizational data.

From the tool's definition Tool name contains 'list' and is prefixed with 'usergroups_users', indicating a query operation to retrieve user group membership data.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs usergroups_users_list safely

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

usergroups_users_list Allowed

usergroups_users_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": {
    "usergroups_users_list": {}
  }
}

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

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

FAQ

Questions about usergroups_users_list

What does the usergroups_users_list tool do? +

usergroups_users_list is a read tool on the Slack MCP server. It is categorised as a Read tool in the Slack MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on usergroups_users_list? +

Register the Slack MCP server in PolicyLayer and add a rule for usergroups_users_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 Slack. Nothing to install.

What risk level is usergroups_users_list? +

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

Can I rate-limit usergroups_users_list? +

Yes. Add a rate_limit block to the usergroups_users_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 usergroups_users_list completely? +

Set action: deny in the PolicyLayer policy for usergroups_users_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 usergroups_users_list? +

usergroups_users_list is provided by the Slack MCP server (karbassi/slack-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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