list_all_clusters

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds meaningful behavioral context beyond those hints: it labels the data as 'Static topology only' and warns about the 'list envelope' with a 'real total.' It also documents the intended workflow. Not as rich as full pagination/performance notes, but it genuinely supplements the annotations.

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

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

The description is three sentences with no fluff. The core purpose is front-loaded, the return envelope note is brief, and the usage guidance is packed into a single efficient sentence. Every sentence earns its place.

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

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

Given no output schema, the description provides a minimal return expectation ('list envelope with a real total') and lists the visible fields. It also routes the agent to the correct next tool. A small gap remains: the description does not mention how limit interacts with total if paginated, but this is minor for a static topology list tool with well-covered schema and annotations.

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

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

Schema description coverage is 100%, and both limit and target already have clear descriptions in the schema. The tool description adds no parameter-specific information, but because the schema fully documents both parameters, the baseline of 3 is appropriate.

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

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

The description opens with a specific verb and resource: 'List clusters with host count, DRS/HA status, and resource totals.' It also clarifies this is a static topology listing, distinguishing it from cluster_health_summary, a very close sibling. An agent knows exactly what data this tool provides and what it does not.

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

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

The description explicitly instructs: 'use this to resolve a cluster name, then cluster_health_summary, which supersedes stitching this with list_esxi_hosts and get_alarms yourself.' This gives clear when-to-use guidance and directs the agent away from an alternative composition. 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.