Moves the mouse pointer to a page element or coordinate to reveal hidden menus and tooltips that appear on mouseover.
Move the mouse over an element (by ref) or a point, to reveal menus and tooltips.
| Name | Required | Description | Default |
|---|---|---|---|
| x | No | ||
| y | No | ||
| ref | No | Element ref from read_page or find, e.g. ref_12 or f1:ref_3 (f1 = inside frame 1) | |
| tabId | Yes | Tab id from tabs_context |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden; it clearly discloses that the tool moves the mouse over an element or point and does not click. It does not enumerate side effects, but for a low-risk hover action the behavior is adequately transparent.
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 front-loaded sentence with no filler; every clause adds meaning (action, target, purpose).
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?
The tool is simple and the description covers the core action, but it leaves gaps: x/y coordinate semantics, precedence if both ref and point are provided, and the effect of providing neither. These matter for correct invocation.
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 documents ref and tabId but leaves x and y undescribed; the description compensates partially by saying a point can be used, which maps to x/y. It does not specify coordinate space or whether x and y must be supplied together.
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 uses a specific verb ('Move') and names the exact resource ('an element (by ref) or a point'), with the intended effect 'to reveal menus and tooltips.' This clearly distinguishes hover from sibling actions like click or scroll.
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 states when to use it: whenever an element or coordinate needs a mouse-over to reveal menus/tooltips. It does not explicitly mention alternatives or exclusions, but the context is clear enough relative to click/scroll siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.