update_lightpaper · Lightpaper MCP: Risk & Policy

WHAT IT DOES

What update_lightpaper does on Lightpaper Mcp

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

WHY IT NEEDS A POLICY

Why update_lightpaper needs a policy

This tool creates or modifies data reversibly—updating a document is a classic Write operation. It does not delete data (which would be Destructive), nor does it execute arbitrary code (Execute).

From the tool's definition Tool name 'update_lightpaper' and description 'Update an existing document' directly indicate modification of existing data. The access control ('Only the document owner can update') confirms this is a Write operation with ownership-based safeguards.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_lightpaper Rate-limited

update_lightpaper 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": {
    "update_lightpaper": {
      "limits": [
        {
          "counter": "update_lightpaper_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 Lightpaper Mcp, so you can run agents against it safely.

FAQ

Questions about update_lightpaper

What does the update_lightpaper tool do? +

Update an existing document. Only the document owner can update. It is categorised as a Write tool in the Lightpaper Mcp MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_lightpaper? +

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

What risk level is update_lightpaper? +

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

Can I rate-limit update_lightpaper? +

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

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

update_lightpaper is provided by the Lightpaper MCP server (pypi:lightpaper-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.