frontmost_app

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

The description adds no behavioral details beyond the annotation (readOnlyHint=true). It does not disclose what happens when no app is frontmost, or any edge cases. Since annotations already declare readonly, the description contributes little.

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 a single concise sentence with no filler. It is front-loaded with the core purpose. Slightly more context (e.g., return type) could improve it, but it is efficient.

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 no parameters, no output schema, and a readonly annotation, the description is minimally adequate. It states the tool's purpose but does not specify return format or behavior in edge cases. With 39 sibling tools, more context would help disambiguate.

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, so no parameter documentation is needed. Schema description coverage is 100% (no params), and the description appropriately avoids redundant info. Baseline 4 applies per rubric.

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 'Name of the app currently in the foreground.' This clearly indicates the tool retrieves the current frontmost app's name. It distinguishes from sibling 'list_running_apps' by focusing on only the active app, though the description could explicitly use 'returns' or 'gets' for stronger action clarity.

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 provided on when to use this tool versus siblings like 'list_running_apps' or 'open_app'. The description does not mention context or alternatives, leaving the agent to infer appropriate usage.

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