pin_message · Telegram MCP: Risk & Policy

WHAT IT DOES

What pin_message does on Telegram

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

WHY IT NEEDS A POLICY

Why pin_message needs a policy

Pinning a message modifies chat state but does not delete or create financial transactions. It is reversible (messages can be unpinned), distinguishing it from Destructive. It does not execute arbitrary code or run external commands, so it is not Execute. It modifies data (message pin status), placing it in Write category.

From the tool's definition Tool name 'pin_message' indicates modification of message state/metadata in Telegram. The sibling tools show this server handles message operations: send, reply, edit, delete, forward, archive.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

pin_message Rate-limited

pin_message 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.

View as policy code

policy.json

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

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Telegram, so you can run agents against it safely.

FAQ

Questions about pin_message

What does the pin_message tool do? +

pin_message. It is categorised as a Write tool in the Telegram MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on pin_message? +

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

What risk level is pin_message? +

pin_message is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit pin_message? +

Yes. Add a rate_limit block to the pin_message 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 pin_message completely? +

Set action: deny in the PolicyLayer policy for pin_message. 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 pin_message? +

pin_message is provided by the Telegram MCP server (vovavindar/telegram-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.