cpu_count

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

With no annotations, the description must carry the safety/behavior disclosure itself. It indicates a read-only fetch of a CPU count, but does not state side-effect freedom, error behavior, or what happens without a connected device. This is adequate for a trivial query but not rich.

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 sentence conveys the function, target device, and parameter requirement with no redundant wording or buried details.

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 0-parameter query returning a simple count, the description is nearly complete: it identifies the device context and the result. It could mention the return value type explicitly, but 'number' is sufficient for an agent to use the result.

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?

The tool has zero parameters and the schema already shows an empty property set; the description reinforces this with 'No parameters are required.' Under the 0-param baseline this is appropriately scored.

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 ('Returns') and resource ('number of CPU cores on the connected Android device'). This cleanly identifies the tool's function and distinguishes it from the sibling cpu_percent, which measures usage rather than core count.

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?

No guidance is given about when to choose cpu_count over related tools such as cpu_percent, or about prerequisites like an attached device. 'No parameters are required' is an input detail, not usage selection guidance.

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