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Glama

vm_power_on

Destructive

Power on a VM in Nutanix Prism Central using its extId; use dry-run to preview the action before execution, then reverse it with power-off if needed.

Instructions

[WRITE][risk=medium] Power on a VM (reversible → power-off). Auto-handles ETag.

Args:
    vm_ext_id: VM extId as returned by vm_list.
    dry_run: If True, return what WOULD be powered on without doing it.
    target: Prism Central target name from config; omit for the default.

Input Schema

NameRequiredDescriptionDefault
targetNo
dry_runNo
vm_ext_idYes

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

A4.1/5.0
Behavior4/5

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

Annotations already declare write/destructive/idempotency profile, yet the description adds real value beyond them: risk=medium, the reversibility path (power-off), and 'Auto-handles ETag' (meaning concurrent-update conflicts are handled internally). It still doesn't say whether repeated calls are safe, which matters given idempotentHint=false.

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

Conciseness4/5

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

Front-loaded tag block plus a compact args list; every line earns its place. The parenthetical could be tightened, but nothing is wasted.

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?

For a 3-param mutation with annotations and no output schema, the description covers purpose, reversibility, dry-run behavior, and every parameter's meaning. Return-value shape is the only omission, and that is minor for this tool class.

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

Parameters4/5

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

Schema coverage is 0%, so the description carries the burden and does so: vm_ext_id is tied to its source ('as returned by vm_list'), dry_run is explained with its exact semantics ('return what WOULD be powered on'), and target is explained as a config-sourced Prism Central name with a default. Only slight gap is no format example for extId.

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?

States a specific verb+resource ('Power on a VM') and immediately scopes it against its inverse ('reversible → power-off'), which disambiguates it from the sibling vm_power_off. The [WRITE][risk=medium] tag further pins the operation class.

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

Usage Guidelines3/5

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

Usage context is implied by the reversibility note and the dry_run argument, but there is no explicit guidance on when to prefer this over alternatives or any preconditions (e.g. VM must be powered off first). Adequate but inferential.

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