real-browser-mcp-server

random_scroll

Scroll pages in any direction, set pixel amount, and trigger lazy-loaded content automatically for reliable browsing and testing.

Instructions

Scroll the page with configurable direction, amount, and automatic lazy-load triggering.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "random_scroll"
  }
}

Input Schema

Name	Required	Description	Default
`amount`	No	Pixels to scroll. 0 = auto-decide based on page content height
`iframe`	No	Scroll inside a specific iframe by index instead of the main frame
`smooth`	No
`direction`	No		smart
`iframeSelector`	No	Scroll inside a specific iframe by CSS selector instead of the main frame
`aiDetectLazyLoad`	No	Detect and trigger lazy-loaded content

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv3.3.1Sep 8, 2026

addedInput schema / properties / iframe

Added value: +{
+  "description": "Scroll inside a specific iframe by index instead of the main frame",
+  "type": "number"
+}

addedInput schema / properties / iframeSelector

Added value: +{
+  "description": "Scroll inside a specific iframe by CSS selector instead of the main frame",
+  "type": "string"
+}

First observedv3.2.13Sep 5, 2026

TDQS

A3.7/5.0

Behavior3/5

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

With no annotations, the description carries the behavioral burden. It does disclose the core action and the automatic lazy-load triggering side effect, but it does not describe iframe targeting, smart/random direction semantics, smoothness behavior, or other potential effects on page state.

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 a single front-loaded sentence with no redundant words. It efficiently conveys the core action and key configurable aspects.

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

Completeness3/5

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

For a simple utility with all-optional parameters, the description plus schema is mostly adequate. However, with no annotations and no output schema, the description leaves behavioral context like smart/random direction and iframe targeting to be inferred rather than explained.

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

Parameters3/5

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

Schema description coverage is 67%, and the description mainly restates high-level concepts like direction, amount, and lazy-loading. It does not add meaning for underspecified parameters such as smooth or the direction enum values smart/random.

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 states a specific verb and resource ('scroll the page') and names configurable behaviors: direction, amount, and lazy-load triggering. This makes the tool's function clear and distinguishes it from sibling interaction tools like click or press_key.

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

Usage Guidelines3/5

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

The description implies its use for scrolling and triggering lazy-loaded content, and the schema exposes iframe targeting, but it does not explicitly state when to use this tool over alternatives or when not to use it. An agent must infer the appropriate context.

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