Charlotte

charlotte_scroll

Scroll pages or containers by direction and amount, then get the full updated page representation for targeted navigation.

Instructions

Scroll the page or a specific container. Returns full page representation after scrolling.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "direction": "<direction>"
    },
    "name": "charlotte_scroll"
  }
}

Input Schema

Name	Required	Description
`amount`	No	Scroll amount: "page" (default), "half", or pixel value (e.g. "200")
`direction`	Yes	Scroll direction
`element_id`	No	Scroll within a specific container element

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv0.8.0Aug 10, 2026

changedInput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

removedInput schema / additionalProperties
```
Removed value: -false
```

First observedv0.6.3May 26, 2026

TDQS

A3.8/5.0

Behavior3/5

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

With no annotations provided, the description carries the full burden. It does disclose that the tool returns a full page representation after scrolling, which is useful behavioral context. However, it does not mention any potential side effects, prerequisites, or the nature of the scroll (e.g., instant, smooth). The safety/read-only nature is inferred but not stated.

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 two concise sentences: one for the action and one for the return value. There is no redundant or filler content, and the key information is front-loaded.

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

Completeness4/5

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

The tool is relatively simple with 3 parameters, all well-documented in the schema. The description covers the action and explicitly mentions the return value, which is important since there is no output schema. However, 'full page representation' is a bit vague, and the lack of annotations leaves safety assumptions implicit. Overall, it is reasonably complete for a scroll action.

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 100%, with each parameter (amount, direction, element_id) already described. The description adds little beyond the schema, only hinting at element_id via 'specific container'. Since the schema does the heavy lifting, a baseline score of 3 is appropriate.

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 uses a specific verb ('Scroll') and a resource ('page or a specific container'), which clearly differentiates it from sibling tools like charlotte_navigate or charlotte_observe. It also states the outcome ('Returns full page representation after scrolling'), making the purpose unambiguous.

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?

No explicit guidance is given about when to use this tool versus alternatives. The usage is implied by the action itself (scrolling), but there is no mention of exclusions or alternative tools, such as using navigation for moving between pages. This is a minimum viable level of guidance.

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