vsan_health

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

Annotations already mark it readOnly/idempotent, and the description adds behavioral specifics: 'If vSAN is not enabled, returns vsan_enabled=false with a message rather than an error,' 'overall_health is reported as "unknown",' and 'No side effects.' This enriches beyond the structured hints.

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 structured with a READ tag, a one-sentence purpose, a return-format block, notes, and arg explanations. Every line adds value, and the formatting makes it easy to scan.

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?

The description covers return payload, error behavior, health limitations, and an alternative tool. Given the tool's read-only nature and no output schema, it provides sufficient contextual information for an agent to select and invoke it correctly.

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?

The input schema has no property descriptions (0% coverage), but the description details both args: cluster_name must be exact as shown in vCenter and errors if not found; target is an optional vCenter/ESXi target from config. This fully compensates for the schema's lack of semantic information.

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 '[READ]' and explicitly states 'Get vSAN enablement status, host count, and per-host disk-group layout for a cluster,' naming a specific verb and resource. It also distinguishes itself from sibling tool vsan_capacity by noting 'Use vsan_capacity for space usage instead.'

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?

It explicitly names vsan_capacity as the alternative for space usage, and clarifies that detailed health checks require vCenter UI. This gives clear context on when the tool is appropriate.

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