Move mouse

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

The description only states the basic action and does not mention potential side effects like triggering hover events or changing cursor appearance. While readOnlyHint=false implies some state change, the description does not elaborate on observable consequences beyond moving the mouse.

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 one concise sentence that directly states the action and coordinate format. It is front-loaded and contains no extraneous information, making it easy to parse and understand.

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 simple mouse-move operation, the description is complete: it defines the action, the coordinate system, and the parameters. There is no output schema, and no additional context is necessary to call the tool correctly.

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 schema covers both parameters fully, and the tool description clarifies that coordinates are in viewport CSS pixels, which adds meaningful unit context. The per-parameter descriptions are minimal but adequate given the clarity of the parameter names and the tool-level unit specification.

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 moves the mouse to viewport coordinates, which is a specific and concrete action. It is distinguishable from siblings like click, hover, or drag because it only moves the cursor without any additional action.

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 does not explicitly compare with alternative tools such as browser_hover or browser_mouse_click_xy, which could help agents choose the right one. It is clear that this is a raw coordinate-based move, but the lack of explicit guidance on when to use it over element-based alternatives leaves some ambiguity.

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