List Devices

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

Annotations already mark readOnlyHint true. Description adds useful context beyond annotations: the tools lists physical and simulated devices, covers both platforms, and indicates devices are local, connected, and free to use. Does not describe return format, but this is a simple list operation.

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 short sentences front-load the core action, then add relevant detail, then provide alternative guidance. No wasted words or repetition.

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 parameterless read-only list tool, the description fully covers what an agent needs: what is listed, platform coverage, local availability, and when to choose the sibling remote-device tool. No output schema is present, but the description gives enough expectation about the return content.

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?

There are zero parameters, so parameter semantics are not needed. The description's context about what is being listed is sufficient and adds no conflicting or missing parameter guidance.

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?

Description uses specific verb 'List' and resource 'available devices', and elaborates that these include physical devices, simulators, emulators, Android and iOS. It clearly differentiates from sibling tool mobile_list_remote_devices by naming it explicitly.

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?

States exactly when to use this tool: for local devices already connected to this machine, ready to use immediately at no cost. Explicitly routes to mobile_list_remote_devices for shared remote cloud fleet devices.

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