Find outdated devices

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

With no annotations, the description carries full weight. It discloses ordering ('oldest first'), output detail ('freshest activity timestamp for each'), the separate grouping of missing/unparseable versions with rationale, and platform coverage. This gives the agent a clear behavioral model 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?

Three sentences with no waste. Each sentence adds distinct value: the core action with ordering, the special handling of unknown versions, and the platform scope. Front-loaded and efficient.

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?

The tool has only two parameters, no output schema, and no annotations. The description covers the essential behavior (listing, ordering, grouping, platforms) sufficiently for an agent to understand what the tool returns and when to use it. No critical gaps remain.

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 100%, so both parameters are already well-documented. The description adds context about the threshold behavior and unknown versions, but does not significantly enhance parameter meaning beyond what the schema provides. Baseline 3 is appropriate.

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 the tool's function: 'List devices whose OS major version is below a threshold' with a specific verb and resource. It also distinguishes from siblings by mentioning 'Spans macOS and iOS/iPadOS/tvOS' and the separate handling of unknown versions, which sets it apart from generic device listing tools.

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 provides clear context for when to use the tool (identifying outdated devices by OS version threshold) and implies a comparison with generic device finders. It does not explicitly name alternatives or provide exclusions, but the specificity of the use case is sufficient for an agent to select it appropriately.

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