scrollHorizontal

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

With no annotations, the description carries the burden of behavioral disclosure. It explains the two usage modes (by pixels or to end) and names common use cases, which adds useful context. However, it does not disclose potential failure modes (e.g., element not scrollable) or return behavior, leaving some behavioral traits implicit.

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 two sentences with no wasted words. It leads with the action, specifies the modes, and ends with use cases. This is an example of efficient, front-loaded writing.

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 scroll tool with 100% schema coverage and no output schema, the description covers the core purpose, modes, and target elements. It does not mention return values or error handling, but these are less critical for a scroll operation. Overall, it is sufficiently complete for the tool's complexity.

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 the baseline is 3. The description's phrase 'by pixels or to end' mirrors the schema's explanation of 'amount' ('Pixels to scroll or full for end'), adding little new meaning. It does not elaborate on 'selector' or 'direction' beyond what the schema already states, so the added value is minimal.

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's action ('Scroll element horizontally') and its modes ('by pixels or to end'). It also gives specific use cases ('tables, carousels, scrollable containers'), distinguishing it from the sibling tool 'scrollTo' which likely handles vertical or general scrolling. The verb and resource are specific 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 provides clear context for when to use the tool ('For tables, carousels, scrollable containers') and implies horizontal scrolling scenarios. However, it does not explicitly mention alternatives (e.g., 'use scrollTo for vertical scrolling') or state when not to use this tool, so it stops short of a 5.

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