set_agent_status · Agent Bus MCP: Risk & Policy

WHAT IT DOES

What set_agent_status does on Agent Bus

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

WHY IT NEEDS A POLICY

Why set_agent_status needs a policy

This tool creates or modifies data (agent status) in a reversible manner. Setting an agent's status is a state change that can be undone by setting it to a different status, making it Write rather than Destructive.

From the tool's definition Tool description explicitly states it 'Set[s] an agent work state' to one of several predefined statuses (idle, working, blocked, waiting_review, or sleeping). This modifies the internal state of an agent.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_agent_status Rate-limited

set_agent_status 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": {
    "set_agent_status": {
      "limits": [
        {
          "counter": "set_agent_status_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 Agent Bus, so you can run agents against it safely.

FAQ

Questions about set_agent_status

What does the set_agent_status tool do? +

Set an agent work state: idle, working, blocked, waiting_review, or sleeping. It is categorised as a Write tool in the Agent Bus MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_agent_status? +

Register the Agent Bus MCP server in PolicyLayer and add a rule for set_agent_status: 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 Agent Bus. Nothing to install.

What risk level is set_agent_status? +

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

Can I rate-limit set_agent_status? +

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

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

set_agent_status is provided by the Agent Bus MCP server (mustaphasteph/agent-bus). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.