AI agents use unpin_chat to create or update resources in Telegram MCP Complete — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Telegram MCP Complete environment.
Unpinning a chat modifies metadata about the chat's pinned status but does not delete data, execute code, or trigger external operations. This is a reversible state change, placing it in the Write category. Severity is low because the impact is limited to UI organization with no data loss or system compromise risk.
From the tool's definition Tool name 'unpin_chat' and description '取消置顶聊天' (cancel pinning of chat) indicate modification of chat properties. Unpinning reverses a previous pin action, making it a Write operation that modifies chat state non-destructively.
Documented attack patterns abuse exactly the kind of access unpin_chat gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Telegram MCP Complete, and nothing reaches the server without passing your rules. This is the rule we recommend for unpin_chat:
{
"version": "1",
"default": "deny",
"tools": {
"unpin_chat": {
"limits": [
{
"counter": "unpin_chat_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}unpin_chat stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
取消置顶聊天. It is categorised as a Write tool in the Telegram MCP Complete MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Telegram MCP Complete MCP server in PolicyLayer and add a rule for unpin_chat: 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 Complete. Nothing to install.
unpin_chat is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the unpin_chat 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 unpin_chat. 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.
unpin_chat is provided by the Telegram MCP Complete MCP server (you922/telegram-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Telegram MCP Complete, 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.
153 Telegram MCP Complete tools catalogued and risk-classified — across an index of 43,000+ MCP servers.