device_info

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

With no annotations, the description must carry the behavioral burden. It implies a read operation by naming output fields, but it does not explicitly state whether it only reads device state, what happens with no UDID, or whether a device must be connected before calling.

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-loads the key return values with no filler. However, it is a fragment rather than a full operational sentence, which slightly limits clarity.

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 one-parameter tool with no annotations or output schema, the description should clarify the action, the parameter's purpose, and any device connection requirements. It covers none of these, so an agent would struggle to invoke 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?

The single 'udid' parameter is optional and has 0% schema description coverage. The description mentions UDID as an output field but does not explain how it functions as an input parameter or what passing null versus a string does.

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 indicates the tool returns device information (model, iOS version, UDID) for a connected device. It lacks an explicit verb like 'get' or 'return', but the noun phrase is unambiguous and distinct enough from vague 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?

There is no guidance on when to use this tool versus alternatives such as device_list or ios_doctor. No context, preconditions, or exclusions are provided.

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