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

The description adds a key behavioral trait by stating that the action 'changes the viewport only.' This manages the agent's expectation regarding page content mutation or state change, adding value beyond what annotations provide.

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 definition uses two highly efficient sentences. The first defines the action and scope, while the second provides the critical selection logic for the agent without any wasted words.

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 the complexity of the input schema (11 parameters and multiple ways to identify targets), the description provides the essential meta-logic needed to correctly select this tool over its similar scrolling siblings.

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?

While the schema coverage is 100%, the description adds conceptual value by categorizing the operations—either moving by a 'bounded amount' (deltas) or by 'direction' (wheel/enum)—helping the agent structure the input intent.

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 scrolls an identified tab by a bounded amount or direction. Crucially, it differentiates itself from the sibling tool, browser_scroll_into_view, by specifying the scope of its operation.

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?

It provides an explicit comparison and guideline: use this tool for bounded movement or direction change, and use scroll_into_view only when a specific target element must become visible.

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