host_list

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

No annotations are provided, so the description carries the burden. It discloses a key behavioral trait: 'A field the engine did not report is null, never 0.' It also discloses pagination/truncation behavior via the limit parameter description. It doesn't mention auth or rate limits, but for a read-only list tool, the disclosed null semantics and truncation behavior are valuable and go beyond the schema.

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 compact and front-loaded: the purpose is in the first line, the alternative tool is named early, and the Args section is terse but informative. Every sentence earns its place; no filler.

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 list tool with 3 optional parameters and no output schema, the description covers the key semantics: null handling, truncation, search syntax, and target selection. It doesn't describe the output structure, but since there is no output schema, a brief note on what fields are returned is present in the first line. It is complete enough for an agent to call 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?

Schema description coverage is 0%, so the description must compensate. It does: it explains limit's range and default, defines search as 'Engine query language' with examples, and explains target as 'Engine target name from config; omit to use the default.' This adds meaning beyond the bare schema types.

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 clear verb and resource: '[READ] KVM hosts with status, SPM role, memory and VM counts.' It distinguishes itself from sibling host_health_rca by explicitly saying that tool is for 'what is wrong with my hosts.' This is specific and differentiates from siblings.

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 says when to use this tool vs alternatives: 'For "what is wrong with my hosts" use host_health_rca instead of reading this list yourself.' It also explains the search parameter with examples, giving clear context for when to use it. This is explicit routing guidance.

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