scroll_wheel

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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false) but say nothing about side effects. The description adds two non-obvious ones: the node's window is raised, and the pointer is left at the target position ('leaving the pointer there'). It doesn't say whether scrolling can itself change focus or trigger lazy loading failures, so it stops short of a 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?

Two sentences, front-loaded with the operation and targeting modes, then the usage/recovery advice. Every clause carries information (node resolution semantics, pointer placement, follow-up wait, alternative tool) with no filler.

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 side-effecting input tool with no output schema and fully documented parameters, the description supplies targeting semantics, side effects, and a post-scroll verification workflow. Only minor gaps remain, such as interaction with existing focus or modifier-key scrolling.

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 all eight parameters are already documented, giving a baseline of 3. The description still adds the targeting model that the schema does not state: name/role/window behave exactly as click_element resolves them, and x/y are an alternative point-based target rather than a supplement — that is real meaning beyond the field descriptions.

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?

States a concrete verb+resource ('Turn the mouse wheel over a node by its name ... or at a point by x and y') and immediately distinguishes itself from click_element (the same node-finding semantics) and press_keys (the keyboard-focus alternative). An agent can place it precisely among its siblings without opening a schema.

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?

Explicit when-to-use ('for what's past a list's, a page's or a window's edge'), explicit follow-up ('then wait_for stable and look again'), and an explicit alternative with its selecting condition ('to move the keyboard focus, use press_keys'). Nothing about routing is left to inference.

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