add_note · MCP Knowledge Base Server MCP: Risk & Policy

WHAT IT DOES

What add_note does on MCP Knowledge Base Server

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

WHY IT NEEDS A POLICY

Why add_note needs a policy

This tool creates new data (markdown notes) in the knowledge base, which is a reversible write operation. While it modifies state by indexing, there is no irreversible destruction, execution of arbitrary code, or financial impact.

From the tool's definition Tool description explicitly states 'Create a new markdown note' and 'index it' - these are create and modify operations that are reversible. The tool name 'add_note' and verb 'Create' confirm write semantics.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_note Rate-limited

add_note 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_note": {
      "limits": [
        {
          "counter": "add_note_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 Knowledge Base Server, so you can run agents against it safely.

FAQ

Questions about add_note

What does the add_note tool do? +

Create a new markdown note in the knowledge base and immediately index it. It is categorised as a Write tool in the MCP Knowledge Base 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_note? +

Register the MCP Knowledge Base Server MCP server in PolicyLayer and add a rule for add_note: 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 Knowledge Base Server. Nothing to install.

What risk level is add_note? +

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

Can I rate-limit add_note? +

Yes. Add a rate_limit block to the add_note 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_note completely? +

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

add_note is provided by the MCP Knowledge Base Server MCP server (m4k00/mcp-knowledge-base). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.