file-track · Jj MCP: Risk & Policy

WHAT IT DOES

What file-track does on Jj

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

WHY IT NEEDS A POLICY

Why file-track needs a policy

This tool modifies the repository's tracking state by adding files to version control tracking. It is a reversible write operation (files can be untracked), not destructive, and has no financial implications. Misuse could cause unintended files to be tracked in a repository.

From the tool's definition Start tracking specified paths in the working copy of a Jujutsu (jj) repository

Risk signalsAdmin/system-level operation

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

file-track Rate-limited

file-track 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": {
    "file-track": {
      "limits": [
        {
          "counter": "file-track_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 Jj, so you can run agents against it safely.

FAQ

Questions about file-track

What does the file-track tool do? +

Start tracking specified paths in the working copy of a Jujutsu (jj) repository. By default new files are automatically tracked; this is primarily useful when auto-tracking is disabled. Parameters: paths (Paths to track), repoPath (Optional path to repo root or working directory), cwd (Optional working directory to run the command in). It is categorised as a Write tool in the Jj MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on file-track? +

Register the Jj MCP server in PolicyLayer and add a rule for file-track: 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 Jj. Nothing to install.

What risk level is file-track? +

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

Can I rate-limit file-track? +

Yes. Add a rate_limit block to the file-track 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 file-track completely? +

Set action: deny in the PolicyLayer policy for file-track. 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 file-track? +

file-track is provided by the Jj MCP server (jj-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.