previous · Lyngdorf MCP Server MCP: Risk & Policy

WHAT IT DOES

What previous does on Lyngdorf MCP Server

AI agents invoke previous to trigger actions in Lyngdorf MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why previous needs a policy

This tool triggers an external operation on a physical audio device (changing the playback position to the previous track). It is not a simple read, nor does it destroy data or involve finances. It executes a playback control command on the streaming source, with effects that depend on the current playback state.

From the tool's definition Go to previous track. Works with streaming sources.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

previous Rate-limited

previous stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "previous": {
      "limits": [
        {
          "counter": "previous_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Lyngdorf MCP Server, so you can run agents against it safely.

FAQ

Questions about previous

What does the previous tool do? +

Go to previous track. Works with streaming sources. It is categorised as a Execute tool in the Lyngdorf MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on previous? +

Register the Lyngdorf MCP Server MCP server in PolicyLayer and add a rule for previous: 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 Lyngdorf MCP Server. Nothing to install.

What risk level is previous? +

previous is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit previous? +

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

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

previous is provided by the Lyngdorf MCP Server MCP server (thejens/lyngdorf-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.