set_edition_owned · Hardcover MCP: Risk & Policy

WHAT IT DOES

What set_edition_owned does on Hardcover

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

WHY IT NEEDS A POLICY

Why set_edition_owned needs a policy

The tool creates or modifies data (ownership state) but does so reversibly—a user can change the ownership status at any time. This is a metadata update operation with no destructive, financial, or code-execution aspects. It falls squarely in the Write category with low severity due to limited blast radius (only affects one user's library metadata).

From the tool's definition Tool name is 'set_edition_owned' and description states 'Mark an edition as owned or not owned.' This modifies the ownership status of a book edition in the user's library.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_edition_owned Rate-limited

set_edition_owned 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": {
    "set_edition_owned": {
      "limits": [
        {
          "counter": "set_edition_owned_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 Hardcover, so you can run agents against it safely.

FAQ

Questions about set_edition_owned

What does the set_edition_owned tool do? +

Mark an edition as owned or not owned. It is categorised as a Write tool in the Hardcover MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_edition_owned? +

Register the Hardcover MCP server in PolicyLayer and add a rule for set_edition_owned: 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 Hardcover. Nothing to install.

What risk level is set_edition_owned? +

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

Can I rate-limit set_edition_owned? +

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

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

set_edition_owned is provided by the Hardcover MCP server (kristianedlund/hardcover-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.