Scroll a window at specified coordinates by 1-20 wheel ticks in any direction, then read the updated state to verify the action.
Scroll 1–20 wheel ticks at a point in the observed active target. Read resulting state to confirm.
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | ||
| y | Yes | ||
| ticks | No | ||
| direction | Yes | ||
| window_id | Yes | ||
| snapshot_id | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must carry the full burden of behavioral disclosure. It reveals the action range and suggests verifying state afterward, but it does not disclose whether the operation is safe/reversible, what prerequisites exist, how errors manifest, or what the tool returns.
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 compact, front-loaded with the action, and contains no filler. The second sentence adds a useful follow-up instruction without bloating the text.
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 six parameters, zero schema descriptions, no annotations, and no output schema, this description is under-specified. An agent would be left guessing about coordinate systems, scroll behavior limits, failure conditions, and whether it must call desktop_observe to see the result.
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 for all six parameters. It maps roughly to 'ticks', 'point' (x/y), and 'observed active target' (window_id/snapshot_id), but it does not explain coordinate origin/units, the meaning of direction relative to screen/window, or how ticks interact with the direction parameter.
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 ('Scroll 1–20 wheel ticks'), a target ('a point in the observed active target'), and clearly distinguishes itself from siblings like desktop_click, desktop_drag, and desktop_press_keys. This is immediately actionable and unambiguous.
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 when to use the tool: on an observed active target that needs wheel scrolling, and it advises reading the resulting state afterward. However, it does not explicitly contrast with alternatives such as desktop_drag or desktop_invoke, nor does it state when not to use it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.