Scroll a CSS-selected element into view in iOS Safari, with optional block alignment (start, center, end, nearest) to ensure it is visible.
Scroll an element into view (block: start, center, end or nearest).
| Name | Required | Description | Default |
|---|---|---|---|
| page | No | index in inspector_pages; default the first page with a real address | |
| wait | No | seconds to wait for the page list, default 60 | |
| block | No | ||
| index | No | which match, default 0 | |
| selector | Yes | CSS selector of the element |
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It doesn't say whether this waits for the element to exist, what happens if the selector matches nothing, whether it mutates page state (scrolling), or how the 'page' and 'wait' parameters affect behavior. Only the block alignment semantics are implied.
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?
A single front-loaded sentence with no filler. However, it is terse to the point of under-specification rather than fully earned conciseness.
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?
Five parameters, one enum, no annotations, and no output schema. The description explains only 'block' behavior and leaves page selection, wait semantics, and match indexing unexplained. It is not complete enough for a multi-parameter tool with no annotation coverage.
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 80%, so the schema documents page, wait, index, and selector. The description mentions the block values, which the schema already supplies as an enum, so it adds no new meaning. Baseline 3 applies.
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 verb and resource: scroll an element into view, with the block alignment options listed. It is clear on its own, but it does not distinguish itself from the sibling 'scroll' tool, which is the obvious alternative an agent would consider.
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?
No when-to-use or when-not guidance. Nothing tells the agent why it would use this instead of 'scroll', 'tap_css', or 'js'. There are no prerequisites or exclusions stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.