obsidian_remove_topic · Obsidian MCP: Risk & Policy

WHAT IT DOES

What obsidian_remove_topic does on Obsidian

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

WHY IT NEEDS A POLICY

Why obsidian_remove_topic needs a policy

This tool removes a configuration/mapping entry (topic to folder association) but explicitly does not delete or modify any actual notes or files. It is a reversible write operation on metadata/configuration, not a destructive action on content. The blast radius is low since no files are affected.

From the tool's definition Forgets a topic → folder mapping. Existing notes in the folder are not touched.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

obsidian_remove_topic Rate-limited

obsidian_remove_topic 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": {
    "obsidian_remove_topic": {
      "limits": [
        {
          "counter": "obsidian_remove_topic_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 Obsidian, so you can run agents against it safely.

FAQ

Questions about obsidian_remove_topic

What does the obsidian_remove_topic tool do? +

Forgets a topic → folder mapping. Existing notes in the folder are not touched. It is categorised as a Write tool in the Obsidian MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on obsidian_remove_topic? +

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

What risk level is obsidian_remove_topic? +

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

Can I rate-limit obsidian_remove_topic? +

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

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

obsidian_remove_topic is provided by the Obsidian MCP server (yuchi-chang/obsidian-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.