desktop_click

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

With no annotations, the description carries the full burden and discloses multiple important behaviors: automatic choice between pointer input methods, rejection of expired snapshots, changed layout/identity, and covered targets, plus the warning that snapshot validity doesn't prove content unchanged. This materially reduces surprise. It stops short of describing error responses or side effects, so a 4 rather than 5.

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?

Three sentences with no filler; the core action is front-loaded and the caveats are dense but relevant. It could be slightly more organized (e.g., separating validation rules from usage guidance), but it is economical.

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 click tool with no output schema and no annotations, the description covers target validation and failure conditions but omits what the tool returns on success or failure, and doesn't explain how to obtain valid window/snapshot IDs. This is a moderate gap: an agent can invoke it correctly but may not interpret results properly.

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 explain that x/y are screenshot-image coordinates and that snapshot_id relates to an observed snapshot/window. However, it doesn't clarify how window_id/snapshot_id are obtained, the meaning of count, or button beyond the schema's enum. The added semantic is meaningful but incomplete for 6 parameters.

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 action (Click) on a resource (screenshot-image coordinates in the target window or its observed menus), which clearly distinguishes it from scroll/drag/hover siblings. It doesn't explicitly name a sibling alternative, but the screenshot-coordinate mechanism is a strong differentiator, so 4 is appropriate.

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 implies usage: you click when you have a validated target and screenshot coordinates from a snapshot. It cautions about expiring snapshots and content changes, but it never names alternatives (e.g., desktop_choose, desktop_invoke) or states when not to use this tool. The guidance is contextual but not comparative.

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