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 description's additional note that no token is required adds value. It also explains the effect of omitting instance_id, which is beyond the schema. No contradictions with 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?

The description is a single, compact sentence that front-loads the main purpose, then adds the key behavioral detail about instance_id and the auth note. No wasted words.

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 the tool's simplicity (one optional parameter, no output schema), the description covers the essential aspects: what it lists, the optional filter behavior, and authentication requirement. It does not detail the return format, but that is not critical for a simple list operation.

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% (the only parameter is described). The description adds semantic meaning by explaining that omitting instance_id returns OS for all presets, which clarifies the optionality and default behavior. This exceeds the baseline for high coverage.

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 clearly states it lists operating systems available for installation on a preset/server, naming the endpoint (os/list). It distinguishes itself from siblings like list_presets and list_software by specifying the resource (OS) and its purpose (installation), though it does not explicitly name alternatives. This is clear but not a full sibling differentiation.

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 implies usage for retrieving OS options before installation, and mentions behavior with/without instance_id. However, it does not explicitly state when to use this tool versus alternatives, nor does it provide exclusions or prerequisites beyond the token note. Usage is implied but not explicit.

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