start_focus_session · Todos MCP: Risk & Policy

WHAT IT DOES

What start_focus_session does on Todos

AI agents invoke start_focus_session to trigger actions in Todos. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why start_focus_session needs a policy

This tool triggers the initiation of a focus session—an operation with side effects that changes system state and agent behavior. While not destructive or financial, it executes a command to begin a new work context. The effects depend on arguments (which task/plan is focused), making it an Execute rather than Write classification.

From the tool's definition Tool description states 'Start a local focus session' which initiates a new operational context/state for task management.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

start_focus_session Rate-limited

start_focus_session stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "start_focus_session": {
      "limits": [
        {
          "counter": "start_focus_session_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Todos, so you can run agents against it safely.

FAQ

Questions about start_focus_session

What does the start_focus_session tool do? +

Start a local focus session for a task, plan, run, or general agent work. It is categorised as a Execute tool in the Todos MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on start_focus_session? +

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

What risk level is start_focus_session? +

start_focus_session is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit start_focus_session? +

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

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

start_focus_session is provided by the Todos MCP server (@hasna/todos). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.