migrate-diff · MCP Atlas MCP: Risk & Policy

WHAT IT DOES

What migrate-diff does on MCP Atlas

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

WHY IT NEEDS A POLICY

Why migrate-diff needs a policy

migrate-diff generates new migration files, which are reversible modifications to database schemas and version control artifacts. While migrations ultimately execute database changes, the diff tool itself creates files (Write) rather than executing them (Execute).

From the tool's definition Tool name 'migrate-diff' and description 'Generate a new migration file by comparing current state to desired schema' indicate the tool creates new migration files, which are data artifacts in a version control system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

migrate-diff Rate-limited

migrate-diff 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": {
    "migrate-diff": {
      "limits": [
        {
          "counter": "migrate-diff_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 MCP Atlas, so you can run agents against it safely.

FAQ

Questions about migrate-diff

What does the migrate-diff tool do? +

Generate a new migration file by comparing current state to desired schema. It is categorised as a Write tool in the MCP Atlas MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on migrate-diff? +

Register the MCP Atlas MCP server in PolicyLayer and add a rule for migrate-diff: 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 MCP Atlas. Nothing to install.

What risk level is migrate-diff? +

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

Can I rate-limit migrate-diff? +

Yes. Add a rate_limit block to the migrate-diff 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 migrate-diff completely? +

Set action: deny in the PolicyLayer policy for migrate-diff. 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 migrate-diff? +

migrate-diff is provided by the MCP Atlas MCP server (mpreziuso/mcp-atlas). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.