create_prompt · Langfuse Mcp Python MCP: Risk & Policy

WHAT IT DOES

What create_prompt does on Langfuse Mcp Python

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

WHY IT NEEDS A POLICY

Why create_prompt needs a policy

This tool creates or versions prompts, which are data artifacts that can be modified reversibly. It does not permanently delete data (Destructive), execute arbitrary code (Execute), involve financial transactions (Financial), or merely read data (Read). The blast radius is medium because prompt modifications could affect downstream AI behavior, but changes are reversible through versioning or recreation.

From the tool's definition Tool name 'create_prompt' and description 'Create a new prompt or new version of existing prompt' indicate creation and modification of data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_prompt Rate-limited

create_prompt 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_prompt": {
      "limits": [
        {
          "counter": "create_prompt_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 Langfuse Mcp Python, so you can run agents against it safely.

FAQ

Questions about create_prompt

What does the create_prompt tool do? +

Create a new prompt or new version of existing prompt. It is categorised as a Write tool in the Langfuse Mcp Python 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_prompt? +

Register the Langfuse Mcp Python MCP server in PolicyLayer and add a rule for create_prompt: 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 Langfuse Mcp Python. Nothing to install.

What risk level is create_prompt? +

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

Can I rate-limit create_prompt? +

Yes. Add a rate_limit block to the create_prompt 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_prompt completely? +

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

create_prompt is provided by the Langfuse Mcp Python MCP server (log-logn/langfuse-mcp-python). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.