rename_tag · MCP Bear MCP: Risk & Policy

WHAT IT DOES

What rename_tag does on MCP Bear

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

WHY IT NEEDS A POLICY

Why rename_tag needs a policy

This tool modifies existing data (tag names) reversibly across notes. Users could undo the rename by renaming again, making it a Write operation rather than Destructive. The blast radius is medium because renaming a tag affects all notes with that tag, but the operation is reversible and does not irreversibly delete or destroy data.

From the tool's definition The tool description explicitly states 'Rename a tag across all notes', which is a modification operation that updates data (tag names) across multiple notes.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

rename_tag Rate-limited

rename_tag 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": {
    "rename_tag": {
      "limits": [
        {
          "counter": "rename_tag_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 MCP Bear, so you can run agents against it safely.

FAQ

Questions about rename_tag

What does the rename_tag tool do? +

Rename a tag across all notes. It is categorised as a Write tool in the MCP Bear MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on rename_tag? +

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

What risk level is rename_tag? +

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

Can I rate-limit rename_tag? +

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

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

rename_tag is provided by the MCP Bear MCP server (maxim-ist/mcp-bear). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.