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Scroll Page

scroll_page

Scroll the current page vertically by a specified percentage of the viewport height, or jump directly to the top or bottom. Use this to navigate long pages when you need to move by relative amounts.

Instructions

Scroll the current page vertically.

Args: direction: - "up": Scroll upward by amount percent of the window height. - "down": Scroll downward by amount percent of the window height. - "top": Scroll directly to the top; amount is ignored. - "bottom": Scroll directly to the bottom; amount is ignored.

amount: Percentage of the current viewport height used for relative
    up/down scrolling. For example, amount=25 scrolls approximately
    one quarter of the viewport height.

Notes: Values greater than 100 for amount are allowed. For example, 200 means approximately two viewport heights.

Tool selection: - Need to reveal a specific element -> use 'focus_element' with action="scroll_to_element". - Need to scroll the page by a relative amount -> use 'scroll_page'.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`amount`	No
`direction`	No		down

Output Schema

TableJSON Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Addedv1.3.3Sep 13, 2026

TDQS

A4.8/5.0

Behavior4/5

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

The description adds meaningful behavioral detail beyond the annotations: amount is a percentage of viewport height, values greater than 100 are allowed, and amount is ignored for 'top' and 'bottom' directions. The annotations are not contradicted, and the added semantics give the agent accurate expectations for how scrolling behaves.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with clear sections for arguments, notes, and tool selection. Every sentence adds value, and the most important usage guidance is front-loaded near the bottom but easy to find. There is no filler or repetition of schema defaults.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter tool with an output schema present, the description covers the behavioral semantics, special cases, allowed values, and selection guidance. An agent has everything it needs to invoke the tool correctly and know what to expect.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, so the description fully compensates by documenting each direction value and the exact meaning of amount with examples like amount=25 and amount=200. Even the nuance that top/bottom ignore amount is described, which the schema alone would not convey.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb and resource: 'Scroll the current page vertically.' It also names the sibling alternative (focus_element) for the element-revealing case, so an agent can tell which tool fits which task without opening schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The 'Tool selection' section explicitly states when to use scroll_page versus focus_element, including the precise action 'scroll_to_element' for focusing a specific element. It also clarifies that scroll_page is for relative page scrolling. This is clear, actionable guidance with an explicit alternative.

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