Set locale

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

With no annotations provided, the description carries the burden of behavioral disclosure. It reveals that iOS changes apply only after relaunching and Android requires API 33+, which are useful behavioral traits. However, it does not mention side effects, error conditions, or whether the change is reversible, leaving some gaps.

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 two compact sentences, front-loaded with the purpose and then providing platform-specific details. Every sentence adds value with 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, the description covers the core behavior and platform nuances. It omits details about required device_id (though schema covers it) and possible return/error behavior, but for a straightforward setter, this is adequately complete for basic use.

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 only 33%, with only device_id having a description. The description provides an example for locale ('fr-FR') but does not explain app_id or its optionality, which is confusing given the instruction 'Provide app_id.' It fails to fully compensate for the low schema 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 starts with 'Set app locale' which is a specific verb+resource, and provides a BCP-47 example. It clearly distinguishes itself from sibling tools like set_location or set_orientation by focusing on locale configuration.

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 platform-specific usage guidance: Android requires API 33+ and is per-app, while iOS requires relaunching the app. It also instructs to provide app_id. It does not explicitly mention alternatives or when not to use, but the context is clear enough.

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