spaces_create · Musubix MCP: Risk & Policy

WHAT IT DOES

What spaces_create does on Musubix

AI agents use spaces_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 spaces_create needs a policy

This tool creates a new Copilot Space with associated metadata and context management. Creation is reversible (spaces can typically be deleted), making it a Write operation rather than Execute or Destructive. The blast radius is medium because unintended space creation could clutter resources and potentially expose context inappropriately, but the action itself is not irreversible or code-executing.

From the tool's definition Tool name 'spaces_create' and description stating '新しいCopilot Spaceを作成します' (creates a new Copilot Space) indicate creation of a new resource.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

spaces_create Rate-limited

spaces_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": {
    "spaces_create": {
      "limits": [
        {
          "counter": "spaces_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 spaces_create

What does the spaces_create tool do? +

新しいCopilot Spaceを作成します。要件、設計、タスク、ファイルを関連付けて、コンテキストを管理できます。. 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 spaces_create? +

Register the Musubix MCP server in PolicyLayer and add a rule for spaces_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 spaces_create? +

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

Can I rate-limit spaces_create? +

Yes. Add a rate_limit block to the spaces_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 spaces_create completely? +

Set action: deny in the PolicyLayer policy for spaces_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 spaces_create? +

spaces_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.