Skip to main content
Glama
vmware-skills

VMware-Monitor

by vmware-skills
OverviewSchemaSourceRelated ServersDiscussionsAdmin
Python
Hybrid

get_host_memory_tiering

Read-onlyIdempotent

Retrieve per-ESXi-host memory tiering data to see which hosts back RAM with NVMe, how large each tier is, and the NVMe-to-DRAM uplift ratio.

Instructions

[READ] Per-host memory tiering (vSphere 9.1) and NVMe uplift ratio.

When to use: to see which ESXi hosts back RAM with NVMe (memory tiering, 8.0U3+), how large each tier is, and how much of a host's apparent memory rides on NVMe rather than DRAM. This is the only source of measured tier byte sizes.

Returns the list envelope {items, returned, limit, total, truncated, hint}. Each row: host, tiering_type (noTiering|hardwareTiering|softwareTiering), tiering_active, dram_gb, nvme_gb, total_tiered_gb, uplift_ratio (total/DRAM, None if DRAM unknown), and a per-tier breakdown. A host with tiering off reads as tiering_type "noTiering", nvme_gb 0.0 — that is a real "checked, none", not a gap.

Gotchas: reads pyVmomi HostSystem.hardware.memoryTierInfo (needs ESXi 8.0U3+/9.x); older hosts report tiering_type "unknown". Read-only.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
limitNoMax host rows (None = all).
targetNovCenter/ESXi target from config (default if omitted).
host_nameNoFilter to one host by exact name (None = all).

Schema Changelog

Changes observed during successful MCP inspections.

  1. Addedv2.2.0

TDQS

A4.5/5.0
Behavior5/5

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

Beyond the annotations' safety profile, the description discloses important behavioral traits: ESXi 8.0U3+/9.x requirements, the pyVmomi field read, older hosts reporting 'unknown', and the meaning of 'noTiering' as a real checked result rather than missing data. This is rich context that materially affects interpretation.

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 dense but well-structured with a [READ] tag, 'When to use', 'Returns', and 'Gotchas' sections. Every sentence adds useful information, and key constraints are front-loaded.

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?

Even without an output schema, the description fully explains the return envelope and row fields, including edge-case values like uplift_ratio None and tiering_type 'noTiering'. It covers version prerequisites and invariant semantics, so an agent has everything needed to invoke and interpret the tool 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 description coverage is 100%, so the schema already documents limit, target, and host_name. The description adds no parameter-specific syntax, defaults, or edge cases beyond what the schema provides, making the baseline score appropriate.

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 names a specific verb and resource: per-host memory tiering and NVMe uplift ratio. It also states the unique value ('only source of measured tier byte sizes'), distinguishing it from sibling host tools like get_host_performance or list_esxi_hosts.

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?

It gives a clear 'When to use' scenario and notes it is the only source of measured tier byte sizes, which effectively rules out alternatives. However, it does not explicitly state when-not-to-use or name any alternative tool for similar host-level information.

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

Deploy Server

Other Tools