VMware-Monitor

list_all_clusters

Read-onlyIdempotent

Lists VMware vCenter/ESXi clusters with host count, DRS/HA status, and resource totals, returning each cluster moid to resolve names for patch tools.

Instructions

[READ] List clusters with host count, DRS/HA status, and resource totals.

Returns the list envelope with a real total. Each row's moid (e.g. domain-c123) is the cluster id the vLCM patch tools take. Static topology only — use this to resolve a cluster name, then get_cluster_health_summary, which supersedes stitching this with list_esxi_hosts and get_alarms yourself.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "list_all_clusters"
  }
}

Input Schema

Name	Required	Description	Default
`limit`	No	Max clusters to return (None = all).
`target`	No	vCenter/ESXi target from config (default if omitted).

Schema Changelog

Changes observed during successful MCP inspections.

Changed4 schema fields changedv1.9.2Aug 31, 2026

addedInput schema / additionalProperties
```
Added value: +false
```

addedInput schema / properties / limit / description

Added value: +"Max clusters to return (None = all)."

addedInput schema / properties / target / description

Added value: +"vCenter/ESXi target from config (default if omitted)."

changedOutput schema / (root)

Previous value: -{
-  "properties": {
-    "result": {
-      "items": {
-        "additionalProperties": true,
-        "type": "object"
-      },
-      "title": "Result",
-      "type": "array"
-    }
-  },
-  "required": [
-    "result"
-  ],
-  "title": "list_all_clustersOutput",
-  "type": "object"
-}New value: +null

Changed1 schema field changedv1.5.18May 4, 2026

addedInput schema / properties / limit

Added value: +{
+  "anyOf": [
+    {
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Limit"
+}

First observedv0.1.2Mar 8, 2026

TDQS

A4.4/5.0

Behavior4/5

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds genuine context beyond that: it returns a list envelope with a real total, rows carry a moid (e.g. domain-c123) that is the cluster id consumed by vLCM patch tools, and the data is static topology only. Pagination behavior with the limit parameter is left implicit, which keeps it from a 5.

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?

The [READ] tag and the purpose sentence are front-loaded and the second paragraph is dense but each clause earns its place (return shape, id semantics, alternative routing). Slightly heavy phrasing ('supersedes stitching this with...') keeps it short of a 5.

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?

With no output schema, the description carries the burden of describing returns and does so: list envelope with total, row fields, and the moid identifier. Combined with the routing guidance to get_cluster_health_summary, an agent has everything needed to call and interpret this tool.

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 both limit and target are already documented in the schema; the description adds no syntax or format guidance for them. The moid explanation is about return values, not parameters, so the baseline 3 applies.

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 and resource ('List clusters') plus the exact row contents (host count, DRS/HA status, resource totals), and explicitly contrasts itself with get_cluster_health_summary and the manual stitching of list_esxi_hosts/get_alarms. An agent can distinguish it from every sibling without opening a schema.

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

Usage Guidelines5/5

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

Gives an explicit when-to-use ('use this to resolve a cluster name'), a when-not ('static topology only'), and names the superseding alternative (get_cluster_health_summary) along with the anti-pattern it replaces. Nothing is left to inference.

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