add_todo · Obsidian Todos MCP Server MCP: Risk & Policy

WHAT IT DOES

What add_todo does on Obsidian Todos MCP Server

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

WHY IT NEEDS A POLICY

Why add_todo needs a policy

This tool creates new task data in the vault but does not delete, execute code, move money, or trigger external operations. The effect is reversible (todos can be deleted or modified later). The blast radius of misuse is minimal—unwanted todos clutter a personal task list but cause no system damage or data loss.

From the tool's definition Tool name 'add_todo' and description 'Add a new todo to today' indicate creation of new data in the Obsidian vault. Server description confirms it 'allows users to create new todos in daily notes', which is a reversible write operation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_todo Rate-limited

add_todo 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": {
    "add_todo": {
      "limits": [
        {
          "counter": "add_todo_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 Todos MCP Server, so you can run agents against it safely.

FAQ

Questions about add_todo

What does the add_todo tool do? +

Add a new todo to today. It is categorised as a Write tool in the Obsidian Todos MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_todo? +

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

What risk level is add_todo? +

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

Can I rate-limit add_todo? +

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

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

add_todo is provided by the Obsidian Todos MCP Server MCP server (mtuckerb/obsidian-todos-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.