update-todo · Things App MCP: Risk & Policy

WHAT IT DOES

What update-todo does on Things App MCP

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

WHY IT NEEDS A POLICY

Why update-todo needs a policy

This tool modifies data (task properties) but the changes are reversible and not destructive. It does not delete data, execute arbitrary code, or move money. The blast radius is limited to task metadata within the Things app, making it a Write-category risk at medium severity since an AI agent could maliciously update many tasks or inject misleading information into task records.

From the tool's definition The tool description explicitly states it can 'Update an existing to-do in Things' and supports 'changing title, notes, dates, tags, checklist, list assignment, and status.' These are reversible modifications to existing data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update-todo Rate-limited

update-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": {
    "update-todo": {
      "limits": [
        {
          "counter": "update-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 Things App MCP, so you can run agents against it safely.

FAQ

Questions about update-todo

What does the update-todo tool do? +

Update an existing to-do in Things. Requires the to-do ID and your Things auth-token. Supports changing title, notes, dates, tags, checklist, list assignment, and status. It is categorised as a Write tool in the Things App MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update-todo? +

Register the Things App MCP server in PolicyLayer and add a rule for update-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 Things App MCP. Nothing to install.

What risk level is update-todo? +

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

Can I rate-limit update-todo? +

Yes. Add a rate_limit block to the update-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 update-todo completely? +

Set action: deny in the PolicyLayer policy for update-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 update-todo? +

update-todo is provided by the Things App MCP server (lucas-flatwhite/things-app-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.