mobile_device_info

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly implies a read-only operation ('Get device information') and specifies the return format as a 'JSON envelope whose data carries the device detail,' adding transparency about the response shape. It does not explicitly state 'read-only' or list side effects, but the nature of the tool is inherently safe and non-destructive, so a 4 is warranted.

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 tight and well-structured, with a clear one-line summary followed by a specific usage hint and a structured Args/Returns section. Every sentence earns its place, and the most important usage context is front-loaded. 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 (one parameter), the presence of an output schema, and the sibling context (many action tools but few info queries), the description is fully complete. It covers purpose, usage, parameter source, and return format, leaving nothing essential for an agent to infer.

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 0%, so the description must compensate. It does so by explaining the only parameter, serialno, as coming 'from list_devices,' which provides crucial provenance and usage guidance. This is exactly the kind of semantic enrichment needed beyond the bare schema field name.

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 ('Get') and resource ('device information'), listing the exact fields (status, hardware, OS version, screen size). It also distinguishes itself from sibling action tools by focusing on information retrieval, and gives a concrete use case (screen resolution before coordinate conversion), making its purpose unmistakable.

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 a clear when-to-use scenario: 'Use this to learn the screen resolution before converting coordinates returned by a vision model.' This gives an agent explicit context for invoking it. However, it does not mention alternatives or when not to use it, though the sibling list suggests other tools are for actions rather than info queries, so the context is sufficient.

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