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select

Pick an option from a dropdown by providing the element's CSS selector and the value to select. Enables automated testing of form fields.

Instructions

Select an element on the page with Select tag

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": {
      "selector": "<selector>",
      "value": "<value>"
    },
    "name": "select"
  }
}

Input Schema

Name	Required	Description	Default
`selector`	Yes	CSS selector for element to select
`value`	Yes	Value to select

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.13.0May 11, 2026

TDQS

C2.5/5.0

Behavior2/5

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

Annotations indicate readOnlyHint=false and idempotentHint=false, implying the tool modifies state and is not idempotent. However, the description does not add any behavioral details beyond these annotations, such as side effects or error conditions.

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

Conciseness3/5

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

The description is concise (one sentence) but lacks structure. It is not front-loaded with key information; the single sentence is vague and does not earn its place by adding clarity.

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

Completeness2/5

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

Given the simplicity of selecting an option from a <select> element, the description is incomplete. It fails to mention return values, error handling, or that the element must be a <select> tag. Sibling tools like 'click' or 'fill' are not distinguished.

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 has 100% coverage with descriptions for both 'selector' and 'value'. The description adds no further meaning, so it provides adequate but baseline support.

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

Purpose3/5

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

The description 'Select an element on the page with Select tag' indicates the tool operates on <select> elements, but it is vague. It repeats the tool name ('select') and does not clearly specify that it selects an option from a dropdown, leading to potential confusion with the 'click' or 'fill' tools among siblings.

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

Usage Guidelines2/5

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

No guidance is provided on when to use this tool versus alternatives like 'click', 'fill', or 'evaluate'. The description lacks any context about prerequisites (e.g., element must be a <select> tag) or when not to use it.

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