jsr_create_package · JSR MCP: Risk & Policy

WHAT IT DOES

What jsr_create_package does on JSR MCP

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

WHY IT NEEDS A POLICY

Why jsr_create_package needs a policy

This tool creates new data (a package) in a registry, which is a reversible Write operation. While package creation is a significant action requiring proper authorization, it is not destructive (can be undone via deletion), not financial, and not code execution.

From the tool's definition Tool name 'jsr_create_package' and description 'Create a new package in a scope' indicate creation of a new entity.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

jsr_create_package Rate-limited

jsr_create_package 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": {
    "jsr_create_package": {
      "limits": [
        {
          "counter": "jsr_create_package_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 JSR MCP, so you can run agents against it safely.

FAQ

Questions about jsr_create_package

What does the jsr_create_package tool do? +

Create a new package in a scope (requires authentication and scope membership). It is categorised as a Write tool in the JSR MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on jsr_create_package? +

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

What risk level is jsr_create_package? +

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

Can I rate-limit jsr_create_package? +

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

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

jsr_create_package is provided by the JSR MCP server (wyattjoh/jsr-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.