decision_create · Musubix MCP: Risk & Policy

WHAT IT DOES

What decision_create does on Musubix

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

WHY IT NEEDS A POLICY

Why decision_create needs a policy

This tool creates a new record in what is likely a document store or database, which is a reversible write operation. It does not retrieve data (Read), execute arbitrary code (Execute), permanently delete data (Destructive), or handle financial transactions (Financial).

From the tool's definition Tool name 'decision_create' and description 'Create a new Architecture Decision Record (ADR)' indicate the tool creates and persists new data (an ADR document).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

decision_create Rate-limited

decision_create 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": {
    "decision_create": {
      "limits": [
        {
          "counter": "decision_create_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 Musubix, so you can run agents against it safely.

FAQ

Questions about decision_create

What does the decision_create tool do? +

Create a new Architecture Decision Record (ADR). It is categorised as a Write tool in the Musubix MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on decision_create? +

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

What risk level is decision_create? +

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

Can I rate-limit decision_create? +

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

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

decision_create is provided by the Musubix MCP server (@nahisaho/musubix-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.