button

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

Discloses automatic Down/Up events, return format, failure on unreachable backend, and platform-specific button rejection. Since no annotations exist, description carries full burden and does well, though lacks mention of potential side effects like power button locking device.

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, front-loaded with the core action, and each sentence adds essential information with no redundancy. Well-structured.

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?

Covers action, inputs, output, error handling, and platform specifics. Given no output schema, description adequately explains return value and failure conditions, making it complete for a 2-parameter tool.

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 coverage is 100%, but description adds significant value by explaining platform-dependent button availability and error behavior, which is beyond the schema's enum and parameter descriptions.

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 states 'Press a device hardware button' with specific verb and resource, lists supported buttons, and distinguishes from sibling gesture tools by focusing on hardware buttons.

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?

Explicitly says 'Use when you need to trigger hardware button events', providing clear context. However, it does not contrast with alternative tools like gesture-tap or mention when not to use this tool.

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