PNETLab MCP Server

stop_lab

Fully stop a running lab across all open sessions and pods to clear 'error_lab_running' and enable lab deletion.

Instructions

Fully stop a running lab across ALL its open sessions/pods (stops nodes and destroys the pods). Use this to clear 'error_lab_running' before deleting a lab that's still open — including one running under another user's session. Find running labs with list_running_labs.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "lab_path": "<lab_path>"
    },
    "name": "stop_lab"
  }
}

Input Schema

Name	Required	Description	Default
`lab_path`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Jul 10, 2026

TDQS

A4.1/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Discloses destructive behavior (stops nodes, destroys pods) and cross-user capability. No annotations exist, so description covers key behavioral traits. Lacks details on permissions, reversibility, or output structure.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with action and effect. No wasted words; efficient and clear.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Covers purpose, usage context, and prerequisite discovery. For a single-parameter tool with output schema, it provides sufficient context for correct invocation, though could mention output format or async behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage 0% means description must explain lab_path, but it only mentions finding running labs via list_running_labs. Does not explicitly define lab_path as the identifier for the lab to stop, leaving ambiguity.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool stops a running lab across all sessions/pods, distinguishing it from siblings like stop_node or stop_all. It specifies the action and scope.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides explicit use case: clearing 'error_lab_running' before deleting a lab. References list_running_labs for discovery. Does not explicitly contrast with stop_all or stop_node, but context implies lab-level scope.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.