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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds useful context beyond that: the no-session prerequisite and the shape of the returned data. It does not cover error cases (e.g. offline or untrusted device) or response format, keeping it short of a 5.

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?

Two compact sentences, zero filler, with the core action and the key precondition front-loaded before the return-value list. Every clause earns its place.

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-parameter read tool with no output schema, the description compensates by naming representative return fields, which is enough for an agent to know what it will get. Minor gaps remain around device-state prerequisites and failure modes, but nothing essential for invocation is missing.

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% and there is a single required 'udid' parameter already documented in the schema. The description adds no syntax, format, or sourcing guidance for the UDID, so baseline 3 applies.

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 (Get) and resource (device info from an iOS device) and enumerates what is returned (activation state, serial, product type, iOS version). It is clear on its own, but it does not distinguish itself from close siblings like device_info, ios_diagnostics, or ios_lock_status, so an agent must infer the boundary.

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 parenthetical '(no automation session required)' is a real usage condition, telling the agent this can be called without an established session. However, there is no explicit when-to-use versus alternatives such as ios_diagnostics or the generic device_info, so usage is only implied.

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