claim_plan_step · Todos MCP: Risk & Policy

WHAT IT DOES

What claim_plan_step does on Todos

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

WHY IT NEEDS A POLICY

Why claim_plan_step needs a policy

The tool modifies task/plan state by claiming and starting a step, which changes data (ownership, status flags). This is Write rather than Execute because it doesn't directly run arbitrary code—it transitions workflow state. Severity is medium because misclaiming steps could block other agents or create workflow conflicts, but the impact is limited to task coordination and reversible.

From the tool's definition Tool name 'claim_plan_step' and description 'Claim and start the next ready plan step' indicate state modification—claiming a plan step changes its ownership/status from unclaimed to claimed, and 'start' implies initiating execution state.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

claim_plan_step Rate-limited

claim_plan_step 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": {
    "claim_plan_step": {
      "limits": [
        {
          "counter": "claim_plan_step_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 Todos, so you can run agents against it safely.

FAQ

Questions about claim_plan_step

What does the claim_plan_step tool do? +

Claim and start the next ready plan step for an agent. It is categorised as a Write tool in the Todos MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on claim_plan_step? +

Register the Todos MCP server in PolicyLayer and add a rule for claim_plan_step: 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 claim_plan_step? +

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

Can I rate-limit claim_plan_step? +

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

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

claim_plan_step 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.