vsan_health

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, openWorldHint=true. The description adds valuable context: no side effects, 'overall_health' is reported as 'unknown' with an explanation, and non-vSAN clusters return a message instead of an error. No contradictions.

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 one focused paragraph, front-loading the purpose. Every sentence adds value, with no extraneous text. Efficient and well-structured.

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?

For a simple read-only tool with 2 parameters and no output schema, the description lists return fields and covers all key behavioral aspects (error handling, default target, health limitation). It is complete and sufficient.

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 0%, but the description fully compensates: 'cluster_name: Cluster name exactly as shown in vCenter. Errors if the cluster is not found.' and 'target: Optional vCenter/ESXi target name from config; omit to use the default target.' This adds critical meaning beyond the schema.

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 starts with '[READ] Get vSAN enablement status, host count, and per-host disk-group layout for a cluster,' specifying a clear verb and resource. It explicitly contrasts with sibling vsan_capacity by saying 'Use vsan_capacity for space usage instead,' effectively distinguishing the tool's purpose.

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 provides explicit when-to-use guidance (get basic vSAN info), when-not-to-use (full health checks require vCenter UI), and an alternative tool (vsan_capacity). This helps the agent decide correctly.

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