sheets_append_values · Mcp Gsheets MCP: Risk & Policy

WHAT IT DOES

What sheets_append_values does on Mcp Gsheets

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

WHY IT NEEDS A POLICY

Why sheets_append_values needs a policy

This tool adds new rows of data to an existing Google Sheets table. It is a write operation (creating new data) that is reversible — appended rows can be deleted. No code execution, destruction of existing data, or financial operations are involved.

From the tool's definition Append values to the end of a table in a Google Sheets spreadsheet

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

sheets_append_values Rate-limited

sheets_append_values 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": {
    "sheets_append_values": {
      "limits": [
        {
          "counter": "sheets_append_values_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 Gsheets, so you can run agents against it safely.

FAQ

Questions about sheets_append_values

What does the sheets_append_values tool do? +

Append values to the end of a table in a Google Sheets spreadsheet. It is categorised as a Write tool in the Mcp Gsheets MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on sheets_append_values? +

Register the Mcp Gsheets MCP server in PolicyLayer and add a rule for sheets_append_values: 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 Gsheets. Nothing to install.

What risk level is sheets_append_values? +

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

Can I rate-limit sheets_append_values? +

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

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

sheets_append_values is provided by the Mcp Gsheets MCP server (mcp-gsheets). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.