AI agents call groupsLeave to permanently remove resources in Telegram MCP Server — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
Leaving a group or channel is effectively irreversible: the AI agent loses access to the chat, message history may become inaccessible, and re-entry may require manual intervention or a new invitation. This qualifies as Destructive due to the permanent, hard-to-undo nature of the action, with high severity given the potential loss of access to important communications.
From the tool's definition 'Leaves a group chat or channel' — departing a group is an irreversible action (membership is lost, history may be lost, and rejoining may not be possible without a new invite)
Documented attack patterns abuse exactly the kind of access groupsLeave gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Telegram MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for groupsLeave:
{
"version": "1",
"default": "deny",
"hide": [
"groupsLeave"
]
}groupsLeave disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.
Free to start. No card required.
Leaves a group chat or channel. It is categorised as a Destructive tool in the Telegram MCP Server MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Telegram MCP Server MCP server in PolicyLayer and add a rule for groupsLeave: 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 Telegram MCP Server. Nothing to install.
groupsLeave is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the groupsLeave 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 groupsLeave. 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.
groupsLeave is provided by the Telegram MCP Server MCP server (kfastov/tgcli). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Telegram MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
38 Telegram MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.