Charlotte

charlotte_select

Select an option in a dropdown element to update the page state and receive the updated page representation.

Instructions

Select an option in a select/dropdown element. Returns full page representation after selection.

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": {
      "element_id": "<element_id>",
      "value": "<value>"
    },
    "name": "charlotte_select"
  }
}

Input Schema

Name	Required	Description	Default
`value`	Yes	Value or text of the option to select
`element_id`	Yes	Target select element ID

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 of behavioral disclosure. It reveals that the tool returns a full page representation after selection, which is useful, but it does not mention side effects, prerequisites (e.g., element visibility), or event triggering. This is a basic but not comprehensive behavioral description.

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 short sentences that immediately state the core function and the return behavior. It is front-loaded with the action, contains no fluff, and is appropriately sized for the tool's simplicity.

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?

For a simple two-parameter tool with no output schema, the description covers the essential points: what it does and what it returns. It could be marginally improved by noting that it is specifically for dropdowns, but the description and schema together provide sufficient context for an agent to use it correctly.

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?

The input schema already covers 100% of parameters with clear descriptions ('Value or text of the option to select' and 'Target select element ID'). The tool description adds no additional semantics beyond restating the purpose, so the schema is the primary source of parameter meaning.

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 clearly states the action ('Select an option') and the target resource ('select/dropdown element'), making it distinct from sibling tools like charlotte_click or charlotte_type. It also notes the return behavior, further clarifying its function.

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 the tool is for interacting with select/dropdown elements, which provides context on when to use it. However, it does not explicitly contrast it with alternatives like charlotte_click or charlotte_toggle, nor does it mention scenarios where it should not be used.

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