add_columns · Google Sheets MCP Server MCP: Risk & Policy

WHAT IT DOES

What add_columns does on Google Sheets MCP Server

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

WHY IT NEEDS A POLICY

Why add_columns needs a policy

This tool creates new columns in a spreadsheet, modifying the sheet structure. This is a Write operation because it creates/modifies data structures reversibly (columns can be deleted). It is not Destructive because the action is reversible and does not erase existing data.

From the tool's definition Tool name 'add_columns' and description 'Adds columns to a sheet' indicate column creation/insertion, which is a reversible data structure modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_columns Rate-limited

add_columns 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": {
    "add_columns": {
      "limits": [
        {
          "counter": "add_columns_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 Sheets MCP Server, so you can run agents against it safely.

FAQ

Questions about add_columns

What does the add_columns tool do? +

Adds columns to a sheet. Position is 1-based index after which to insert (omit to add at end). It is categorised as a Write tool in the Google Sheets MCP 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 add_columns? +

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

What risk level is add_columns? +

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

Can I rate-limit add_columns? +

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

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

add_columns is provided by the Google Sheets MCP Server MCP server (santiagopereda/mcp_googlesheets). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.