android_press_key

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

No annotations are provided, so the description carries the full burden. The effect of a key press is largely self-evident and the key set is enumerated, but nothing is said about required device state, whether the action blocks, or what the side effects of POWER/VOLUME keys are.

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?

A single front-loaded sentence with the verb, resource, and allowed values, and zero filler. Nothing could be trimmed without losing information.

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 one-parameter tool with no output schema, the description covers the action and the valid key set adequately. A minor gap remains: it does not indicate what the caller gets back or any precondition such as a connected device.

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 the single parameter is a fully enumerated string, so the schema already documents everything. The description merely repeats the enum values, adding no syntax, defaults, or format detail beyond the structured field.

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 states a specific verb and resource ('Press an Android hardware/system key') and enumerates the exact keys, so the purpose is unmistakable. It implicitly separates itself from siblings like android_type_text or android_tap by scoping to hardware/system keys, though it never names an alternative 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?

Usage is only implied: an agent can infer this is for BACK/HOME/POWER-style system keys rather than text entry or coordinate taps. There is no statement of when to prefer it over android_tap or android_type_text, and no prerequisites (e.g., an active device connection) are given.

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