upsert_faction · RPG Ledger MCP Server MCP: Risk & Policy

WHAT IT DOES

What upsert_faction does on RPG Ledger MCP Server

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

WHY IT NEEDS A POLICY

Why upsert_faction needs a policy

The 'upsert' semantic means the tool creates a faction record if it doesn't exist or modifies it if it does, making it a reversible write operation. While the description is empty (lowering confidence slightly), the naming convention and server purpose (managing RPG campaign state) clearly indicate data modification. It is not destructive (no deletion), not execute (no code/command execution), and not financial.

From the tool's definition Tool name 'upsert_faction' indicates an insert-or-update operation on faction data. The 'upsert' pattern is a standard write operation that creates or modifies records.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

upsert_faction Rate-limited

upsert_faction 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": {
    "upsert_faction": {
      "limits": [
        {
          "counter": "upsert_faction_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 RPG Ledger MCP Server, so you can run agents against it safely.

FAQ

Questions about upsert_faction

What does the upsert_faction tool do? +

upsert_faction. It is categorised as a Write tool in the RPG Ledger 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 upsert_faction? +

Register the RPG Ledger MCP Server MCP server in PolicyLayer and add a rule for upsert_faction: 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 RPG Ledger MCP Server. Nothing to install.

What risk level is upsert_faction? +

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

Can I rate-limit upsert_faction? +

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

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

upsert_faction is provided by the RPG Ledger MCP Server MCP server (sepa79/rpg-ledger-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.