ghost_update_tag · Ghost MCP: Risk & Policy

WHAT IT DOES

What ghost_update_tag does on Ghost

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

WHY IT NEEDS A POLICY

Why ghost_update_tag needs a policy

This tool creates or modifies data in a reversible manner. While it alters tag metadata in a Ghost blog, the changes can be undone by updating the tag again with previous values. It does not delete data (which would be Destructive) nor execute arbitrary code (Execute). The blast radius is medium because incorrect tag updates could affect blog organization and SEO, but the changes are recoverable and limited in scope.

From the tool's definition The tool 'ghost_update_tag' is described as 'Update an existing Ghost tag (name, slug, description, and/or visibility)' — it modifies existing data reversibly by changing tag properties.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

ghost_update_tag Rate-limited

ghost_update_tag 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": {
    "ghost_update_tag": {
      "limits": [
        {
          "counter": "ghost_update_tag_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 Ghost, so you can run agents against it safely.

FAQ

Questions about ghost_update_tag

What does the ghost_update_tag tool do? +

Update an existing Ghost tag (name, slug, description, and/or visibility), identified by ID or current slug. It is categorised as a Write tool in the Ghost MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on ghost_update_tag? +

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

What risk level is ghost_update_tag? +

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

Can I rate-limit ghost_update_tag? +

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

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

ghost_update_tag is provided by the Ghost MCP server (uppinote20/ghost-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.