list_os

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: 'No token required' (auth requirement) and the scope-switching behavior of instance_id, which the annotations do not convey.

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?

Three short sentences, all front-loaded and information-dense: resource, endpoint, conditional behavior, and auth note. No filler or 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?

For a single-optional-parameter read tool with no output schema, the description covers scope, the global-fallback behavior, and auth requirements. Only the return shape is unstated, which is acceptable given no output schema exists.

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 100% and already documents instance_id as 'Preset ID from list_presets', so baseline is 3. The description adds meaning beyond the schema by explaining what omitting the optional parameter does (returns OS for all presets), clarifying the semantics of its optionality.

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?

States a specific verb+resource: operating systems available for a preset/server, and even maps it to the raw endpoint (os/list). It is distinguishable from siblings like list_presets and list_software, though it never names an alternative explicitly.

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 conditional 'Without instance_id returns OS for all presets' implies the two usage modes (scoped vs. global), but there is no explicit when-to-use guidance or reference to sibling tools such as list_presets or list_software.

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