source_add_file · NotebookLM MCP Server MCP: Risk & Policy

WHAT IT DOES

What source_add_file does on NotebookLM MCP Server

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

WHY IT NEEDS A POLICY

Why source_add_file needs a policy

This tool creates or adds new data (file sources) to a NotebookLM notebook in a reversible manner. The upload action modifies the notebook's sources collection but does not destroy or overwrite existing data. While it could introduce undesired files into a research context, the effect is reversible (sources can typically be removed), making it Write rather than Destructive or Execute.

From the tool's definition Tool name 'source_add_file' and description 'Upload a local file (PDF, text, markdown, docx) as a source' indicate file creation/addition to the notebook system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

source_add_file Rate-limited

source_add_file 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": {
    "source_add_file": {
      "limits": [
        {
          "counter": "source_add_file_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 NotebookLM MCP Server, so you can run agents against it safely.

FAQ

Questions about source_add_file

What does the source_add_file tool do? +

Upload a local file (PDF, text, markdown, docx) as a source. It is categorised as a Write tool in the NotebookLM 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 source_add_file? +

Register the NotebookLM MCP Server MCP server in PolicyLayer and add a rule for source_add_file: 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 NotebookLM MCP Server. Nothing to install.

What risk level is source_add_file? +

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

Can I rate-limit source_add_file? +

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

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

source_add_file is provided by the NotebookLM MCP Server MCP server (pavelguzenfeld/notebooklm-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.