host_performance

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

Annotations already include readOnlyHint, openWorldHint, idempotentHint. Description adds that data is from a 20-second interval, skips disconnected hosts, and returns live point-in-time data, providing context beyond 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?

Concise and well-structured: summary line, comparative explanation, edge cases, then parameter list. Every sentence adds value; no redundancy.

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 annotations (rich hints), output schema existence (not shown but present), and tool complexity, the description fully covers what the tool does, what it returns, its limitations, and parameter usage.

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 coverage is 0%, but description lists all three parameters with brief explanations ('host_name: Filter to a single host', 'target: Optional target', 'limit: Max rows'), adding meaning beyond the schema's title and type.

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?

Starts with '[READ]' and clearly states 'Real-time CPU/memory/disk/network utilisation per ESXi host.' Directly contrasts with sibling list_esxi_hosts by specifying static vs live metrics.

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?

Explicitly says 'Unlike list_esxi_hosts (static config), this returns LIVE utilisation' and notes 'Busiest hosts first' and 'Disconnected hosts... skipped.' Also states 'Point-in-time only — no historical trend' to clarify limitations.

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