drive_file_share · Google Workspace MCP: Risk & Policy

WHAT IT DOES

What drive_file_share does on Google Workspace

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

WHY IT NEEDS A POLICY

Why drive_file_share needs a policy

This tool creates or modifies sharing permissions on a file, which is a reversible write operation. While it grants access to data rather than creating or modifying the file content itself, it materially changes the file's state and who can access it. The severity is high because unintended sharing could expose sensitive data to unauthorized parties, and the blast radius depends on which files are shared with whom.

From the tool's definition The tool 'drive_file_share' modifies file permissions by granting access to another user via email. The description explicitly states it shares a file 'with someone', which is a reversible modification of access control metadata.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

drive_file_share Rate-limited

drive_file_share 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": {
    "drive_file_share": {
      "limits": [
        {
          "counter": "drive_file_share_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 Google Workspace, so you can run agents against it safely.

FAQ

Questions about drive_file_share

What does the drive_file_share tool do? +

Share a file with someone by email. It is categorised as a Write tool in the Google Workspace MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on drive_file_share? +

Register the Google Workspace MCP server in PolicyLayer and add a rule for drive_file_share: 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 Google Workspace. Nothing to install.

What risk level is drive_file_share? +

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

Can I rate-limit drive_file_share? +

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

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

drive_file_share is provided by the Google Workspace MCP server (rajool/google-workspace-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.