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matt-coppinger

Horizon MCP Server

list_customization_specifications

List vCenter Sysprep/QuickPrep specifications and get their IDs for applying OS customization (hostname, domain join) to VMs during desktop pool or RDSH farm creation.

Instructions

List vCenter customization specifications (Sysprep/QuickPrep) available for pool provisioning.

The customization_specification_id from these results is used in create_desktop_pool and create_rdsh_farm provisioning_settings to apply OS customization (hostname, domain join, license key) to provisioned VMs.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
vcenter_idYesvCenter ID — obtain from list_virtual_centers

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
resultYes

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

A4.1/5.0
Behavior3/5

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

No annotations are provided, so the description carries full burden. It describes the action ('List') which implies a read-only operation, but does not explicitly state side-effect-free behavior, authentication requirements, or error conditions. The description adds the practical context of result usage, but lacks the explicit safety disclosure one might expect without annotations.

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?

The description is two sentences with zero waste. The primary action is front-loaded, and the second sentence explains the downstream relevance. No redundant phrasing or over-elaboration.

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

Completeness5/5

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

Given the presence of an output schema, the description does not need to enumerate return fields. It covers the purpose, usage context, and exactly how the result feeds into other provisioning tools (create_desktop_pool, create_rdsh_farm). An agent has all necessary information to decide when to call this tool and to interpret its role correctly.

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

Parameters3/5

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

Schema coverage is 100%: the only parameter 'vcenter_id' already has a descriptive comment in the schema ('vCenter ID — obtain from list_virtual_centers'). The tool description adds no extra meaning about this parameter beyond what the schema provides, so it stays at the baseline for full coverage.

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 verb 'List' and the resource 'vCenter customization specifications', and adds context about their use for pool provisioning. It differentiates from sibling list tools (e.g., list_virtual_centers, list_desktop_pools) by naming the specific object type and its role in provisioning workflows.

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?

The description explicitly connects this tool to downstream usage: 'The customization_specification_id from these results is used in create_desktop_pool and create_rdsh_farm...' This tells the agent when to call it. It does not name alternatives because none exist among siblings; it effectively implies the when-not-to-use by its specialized purpose.

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