remove_blocker · Nubis MCP: Risk & Policy

WHAT IT DOES

What remove_blocker does on Nubis

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

WHY IT NEEDS A POLICY

Why remove_blocker needs a policy

This tool modifies task state by removing a blocker/dependency relationship. While it changes data, this is a reversible write operation (the blocker could be re-added via add_blocker). It's not destructive in the irreversible sense, but misuse could unblock tasks prematurely, causing workflow issues.

From the tool's definition Remove a blocking dependency, allowing the task to be worked on.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

remove_blocker Rate-limited

remove_blocker 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": {
    "remove_blocker": {
      "limits": [
        {
          "counter": "remove_blocker_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 Nubis, so you can run agents against it safely.

FAQ

Questions about remove_blocker

What does the remove_blocker tool do? +

Remove a blocking dependency, allowing the task to be worked on. It is categorised as a Write tool in the Nubis MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on remove_blocker? +

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

What risk level is remove_blocker? +

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

Can I rate-limit remove_blocker? +

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

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

remove_blocker is provided by the Nubis MCP server (@lil2good/nubis-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.