add_markdown · Jlab MCP: Risk & Policy

WHAT IT DOES

What add_markdown does on Jlab

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

WHY IT NEEDS A POLICY

Why add_markdown needs a policy

Adding a markdown cell creates new data in the notebook in a reversible manner. This is a Write operation rather than Execute because it does not run code or trigger external operations—it merely appends a markdown cell. The severity is low because markdown cells are documentation content with no side effects, and changes can be easily undone by deleting the cell.

From the tool's definition Tool name is 'add_markdown' and description states it 'Add a markdown cell to the notebook.' This is a create operation that adds content to the notebook.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_markdown Rate-limited

add_markdown 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": {
    "add_markdown": {
      "limits": [
        {
          "counter": "add_markdown_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 Jlab, so you can run agents against it safely.

FAQ

Questions about add_markdown

What does the add_markdown tool do? +

Add a markdown cell to the notebook. It is categorised as a Write tool in the Jlab MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_markdown? +

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

What risk level is add_markdown? +

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

Can I rate-limit add_markdown? +

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

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

add_markdown is provided by the Jlab MCP server (kdkyum/jlab-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.