get_window_region

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

With no annotations provided, the description carries full burden. It discloses that the tool returns visible, visible_ratio, region, frame, and screen details. It mentions the activate param defaults to true and sets expectations for measuring background windows. No destructive behavior is noted, but activation behavior is covered. This is good transparency, though it could mention potential side effects of activation.

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 concise, with 5 sentences covering purpose, usage, parameters, and response. No redundant information. It is well-structured and front-loaded with the core purpose. Every sentence adds value.

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 moderate complexity (4 parameters, 1 required) and the existence of an output schema (context signal), the description is complete. It explains the typical use case, parameter defaults, response structure, and error recovery. No gaps identified.

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%, so baseline is 3. The description adds semantic value beyond schema descriptions: it explains that min_visible_ratio should be lowered only when partial visibility is intentional, and activate should be set to False only when measuring a background window intentionally. This provides important usage guidance that the schema alone lacks.

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 the tool returns the visible front-window region for a macOS app, using a specific verb+resource. It distinguishes itself from siblings by explicitly mentioning its use before app window recording, indicating it is a verification step rather than a recording tool.

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 explicit usage context: use before macOS app or browser recording to verify window visibility. It explains the min_visible_ratio default and advises when to lower it. It also instructs what to do if visible is false (reposition or unminimize), effectively guiding the agent on when and how to use the tool.

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