unarchive_chat · Tg MCP: Risk & Policy

WHAT IT DOES

What unarchive_chat does on Tgmcp

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

WHY IT NEEDS A POLICY

Why unarchive_chat needs a policy

The tool modifies the state of a chat by reversing an archive action, making it visible again in the user's chat list. This is reversible (can be re-archived) and non-destructive, fitting the Write category. Severity is medium because unauthorized unarchiving could expose archived conversations or disrupt a user's chat organization, but the action is reversible and doesn't destroy data or move funds.

From the tool's definition Tool name 'unarchive_chat' and description 'Unarchive a chat' indicate a state modification operation that reverses a previous archiving action. This is a write operation that modifies chat metadata.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

unarchive_chat Rate-limited

unarchive_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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "unarchive_chat": {
      "limits": [
        {
          "counter": "unarchive_chat_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 Tgmcp, so you can run agents against it safely.

FAQ

Questions about unarchive_chat

What does the unarchive_chat tool do? +

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

How do I enforce a policy on unarchive_chat? +

Register the Tg MCP server in PolicyLayer and add a rule for unarchive_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 Tgmcp. Nothing to install.

What risk level is unarchive_chat? +

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

Can I rate-limit unarchive_chat? +

Yes. Add a rate_limit block to the unarchive_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.

How do I block unarchive_chat completely? +

Set action: deny in the PolicyLayer policy for unarchive_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.

What MCP server provides unarchive_chat? +

unarchive_chat is provided by the Tg MCP server (oevortex/tgmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.