append_to_spreadsheet · Gg MCP: Risk & Policy

WHAT IT DOES

What append_to_spreadsheet does on Gg

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

WHY IT NEEDS A POLICY

Why append_to_spreadsheet needs a policy

This is a Write operation because it creates or modifies data reversibly. Appending rows to a spreadsheet adds new data but does not delete or permanently overwrite existing content. The operation is reversible—appended rows can be deleted if needed. It does not execute code, trigger external operations with unpredictable side effects, move money, or irreversibly destroy data.

From the tool's definition Tool appends rows to a spreadsheet, modifying existing data. Description states 'Append rows to a spreadsheet' and accepts a 2D array of values to insert at a specified range like 'Sheet1!A1', creating new rows with data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

append_to_spreadsheet Rate-limited

append_to_spreadsheet 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": {
    "append_to_spreadsheet": {
      "limits": [
        {
          "counter": "append_to_spreadsheet_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Gg, so you can run agents against it safely.

FAQ

Questions about append_to_spreadsheet

What does the append_to_spreadsheet tool do? +

Append rows to a spreadsheet. Values format: JSON 2D array. Range: 'Sheet1!A1'. It is categorised as a Write tool in the Gg MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on append_to_spreadsheet? +

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

What risk level is append_to_spreadsheet? +

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

Can I rate-limit append_to_spreadsheet? +

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

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

append_to_spreadsheet is provided by the Gg MCP server (tannht/google-cloud-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.