scout_scroll

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

With no annotations provided, the description carries the full behavioral burden, and it is unusually rich: it discloses the fallback to the largest scrollable pane on app-shell layouts, that smaller regions beside it never move, that it reports SCROLL LOCKED, and that scrolling triggers lazy-loaded content. This goes well beyond what the schema alone reveals.

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 long and dense, but nearly every clause carries behavioral or workflow value, and it is front-loaded with the core action. Some rhetorical framing ('real apps hide their bugs below the fold') could be trimmed, and the parenthetical caveats make it a wall of text rather than a scannable definition, but it is efficient for the complexity it documents.

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 4 optional parameters, no output schema, and no annotations, the description covers the essential missing context: result format (px and %), SCROLL LOCKED detection, fallback behavior, target-region semantics, and why scrolling matters for audits and lazy-loaded content. The schema handles the remaining parameter details, so nothing critical is missing.

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 adds real value on top by explaining the target semantics in depth — single region, nearest scrollable ancestor, and the 'smaller region beside it' trap. It does not redundantly restate by/to/session, leaving the schema to cover those.

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 behavior ('Scroll like a user'), the resource acted on (page or one target region), and the outcome (reports position in px and %, flags SCROLL LOCKED when scroll is blocked). It clearly differentiates itself from sibling tools like scout_snapshot and scout_design_audit by being the scroll-position-changing action that precedes them.

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 gives explicit workflow guidance: use before judging a long page, then re-snapshot/re-audit deep sections, because the design audit measures at the current scroll position. It also warns against calling a nav item missing without scrolling its own container first, which is a concrete when-to-use versus when-to-target instruction.

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