users_set_presence

What users_set_presence does on Slack

AI agents use users_set_presence to create or update resources in Slack, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Slack environment.

Why users_set_presence is rated Medium

Setting presence is a write operation that changes user status/state in Slack. While reversible and not destructive, it modifies data. The blast radius is medium because spoofing presence (appearing online/offline when you're not) could be used for social engineering, impersonation, or disrupting team coordination, but the impact is limited to presence status and doesn't directly access sensitive data, delete…

From the tool's definition Tool name is 'users_set_presence' and description states 'Manually set user presence' — this modifies user state (presence status) in Slack, which is a reversible change to user data.

The rule that runs users_set_presence 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 users_set_presence, this is the rule to start with:

{
  "version": "1",
  "default": "deny",
  "tools": {
    "users_set_presence": {
      "limits": [
        {
          "counter": "users_set_presence_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

Questions about users_set_presence