create_timeline_event · Narrarium MCP: Risk & Policy

WHAT IT DOES

What create_timeline_event does on Narrarium

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

WHY IT NEEDS A POLICY

Why create_timeline_event needs a policy

This tool creates new timeline event data within the Narrarium book repository system. It is Write category because it creates new, reversible data artifacts (timeline event files). Severity is medium because misuse could pollute the story timeline with irrelevant or contradictory events, requiring remediation, but the effects are confined to the repository and are reversible through file deletion or updates.

From the tool's definition Tool name is 'create_timeline_event' and description states it creates 'a timeline event file with participants, significance, consequences, and optional factual research support.' The verb 'create' and action of writing a new file indicates data creation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_timeline_event Rate-limited

create_timeline_event 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": {
    "create_timeline_event": {
      "limits": [
        {
          "counter": "create_timeline_event_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 Narrarium, so you can run agents against it safely.

FAQ

Questions about create_timeline_event

What does the create_timeline_event tool do? +

Create a timeline event file with participants, significance, consequences, and optional factual research support. It is categorised as a Write tool in the Narrarium MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_timeline_event? +

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

What risk level is create_timeline_event? +

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

Can I rate-limit create_timeline_event? +

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

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

create_timeline_event is provided by the Narrarium MCP server (narrarium-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.