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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=true, so safety profile is covered. The description adds that this is a last-resort path requiring a 'visible point' (implying a coordinate source such as a screenshot), but says nothing about how delta_x/delta_y change behavior or whether state changes persist. Adequate over the annotation baseline, not rich.

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?

One sentence, no padding, and the routing cue ('Fallback') is front-loaded. It is efficient, though the brevity is partly under-specification rather than tight 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?

An output schema exists so return values need no prose, but for a 5-parameter, 0%-coverage coordinate tool inside a large browser-automation suite the description is far too thin: no delta semantics, no job_id explanation, no prerequisite about obtaining a visible point. An agent could not invoke this reliably from the text alone.

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% across 5 parameters, so the description carries the full burden. 'Scroll at a visible point' loosely hints that x/y form a coordinate target, but delta_x, delta_y and job_id — including the 500px default scroll amount — are entirely unexplained.

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 specific action (scroll) with a scope qualifier ('at a visible point') and frames itself as a fallback relative to semantic controls, which the sibling list ('click_element', 'check_element', 'press_element') makes meaningful. It doesn't explicitly say it scrolls the browser viewport nor explain the coordinate system, so it stops short of a 5.

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?

'Fallback ... when semantic controls cannot reach the content' is an explicit when-to-use condition, which is more than most siblings offer. It doesn't name concrete alternative tools or state what to try first/last, so it's clear context without full routing guidance.

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