append_to_xlsx · KnowledgeBase MCP: Risk & Policy

WHAT IT DOES

What append_to_xlsx does on KnowledgeBaseMCP

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

WHY IT NEEDS A POLICY

Why append_to_xlsx needs a policy

This tool creates or modifies data in a reversible manner by appending to an existing Excel file. It does not delete or destroy data (ruling out Destructive), does not execute arbitrary code (ruling out Execute), and does not involve financial transactions (ruling out Financial).

From the tool's definition Tool name 'append_to_xlsx' and description 'Mevcut XLSX dosyasına veri ekle' (Turkish: 'Add data to existing XLSX file') indicate modification of existing spreadsheet data by appending rows or values.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

append_to_xlsx Rate-limited

append_to_xlsx 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_xlsx": {
      "limits": [
        {
          "counter": "append_to_xlsx_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 KnowledgeBaseMCP, so you can run agents against it safely.

FAQ

Questions about append_to_xlsx

What does the append_to_xlsx tool do? +

Mevcut XLSX dosyasına veri ekle. It is categorised as a Write tool in the KnowledgeBaseMCP 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_xlsx? +

Register the KnowledgeBase MCP server in PolicyLayer and add a rule for append_to_xlsx: 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 KnowledgeBaseMCP. Nothing to install.

What risk level is append_to_xlsx? +

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

Can I rate-limit append_to_xlsx? +

Yes. Add a rate_limit block to the append_to_xlsx 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_xlsx completely? +

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

append_to_xlsx is provided by the KnowledgeBase MCP server (mehmetozcan-zz/knowledgebasemcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.