save_auth_token · MCP Google Calendar Server MCP

WHAT IT DOES

What save_auth_token does on MCP Google Calendar Server

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

WHY IT NEEDS A POLICY

Why save_auth_token needs a policy

This tool creates or modifies stored authentication state by persisting an OAuth authorization code. This is a Write operation because it irreversibly alters system state (the auth token store), but it is not Destructive because the action is reversible via re-authentication.

From the tool's definition Tool name 'save_auth_token' combined with description 'Save the authorization code received from Google OAuth' indicates persistent storage of authentication credentials.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

save_auth_token Rate-limited

save_auth_token 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": {
    "save_auth_token": {
      "limits": [
        {
          "counter": "save_auth_token_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 Google Calendar Server, so you can run agents against it safely.

FAQ

Questions about save_auth_token

What does the save_auth_token tool do? +

Save the authorization code received from Google OAuth. It is categorised as a Write tool in the MCP Google Calendar Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on save_auth_token? +

Register the MCP Google Calendar Server MCP server in PolicyLayer and add a rule for save_auth_token: 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 Google Calendar Server. Nothing to install.

What risk level is save_auth_token? +

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

Can I rate-limit save_auth_token? +

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

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

save_auth_token is provided by the MCP Google Calendar Server MCP server (nkriman/mcp-google-calendar-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.