os_list_operating_systems

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

With no annotations present, the description carries the full behavioral disclosure burden. It merely restates the action and the return value without adding detail such as ordering, pagination, whether custom ISOs are included, or any side effects. The 'Returns' section is a redundant echo of the purpose rather than a behavioral disclosure.

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 first sentence is appropriately short and front-loaded. However, the 'Returns:' section repeats the same idea almost verbatim, creating redundancy. It would earn a 4 or 5 if it dropped the echo and used the space for actual differentiating detail.

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 simple zero-parameter read-only list, the description is minimally viable. The output schema exists, so return values need not be described in prose. However, it lacks sibling differentiation and any behavioral context, which an agent would need to confidently choose this tool over the many related OS listing tools.

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 tool has zero parameters, so there is nothing for the description to explain beyond what the empty input schema already shows. The baseline for a 0-parameter tool is 4, and the description neither adds nor misses parameter documentation.

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 uses a specific verb and resource: 'List all available operating systems.' The word 'all' implicitly distinguishes this from sibling tools like os_list_linux_os and os_list_windows_os, which return filtered subsets. However, it never explicitly names or contrasts those alternatives, so it is clear but not fully differentiated.

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 gives no guidance on when to choose this tool over its many OS-related siblings (e.g., os_search_os_by_name, os_list_os_by_family, os_get_os_by_name). There is no mention of use cases, exclusions, or alternatives, so an agent gets no help selecting among the similar list tools.

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