gecko-mcp

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get_attribute

Read-only

Read an attribute value (e.g., href, value, aria-label) from a web element on the active tab using a CSS selector or fingerprint reference.

Instructions

Read an attribute (e.g. href, value, aria-label) of an element. Active tab unless browserId given.

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": {
      "name": "<name>"
    },
    "name": "get_attribute"
  }
}

Input Schema

Name	Required	Description
`name`	Yes	Attribute name, e.g. "href".
`selector`	No	CSS selector.
`ref`	No	Fingerprint ref from snapshot.
`browserId`	No	Target tab. Defaults to active.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv2.2.4Jun 20, 2026

TDQS

A4.2/5.0

Behavior4/5

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

Annotations indicate readOnlyHint and openWorldHint, which are consistent. Description adds the key behavior: operates on active tab unless browserId provided. No side effects mentioned, but annotations cover safety.

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?

Two sentences, no wasted words. Front-loaded with verb and resource. Examples and conditional behavior are efficiently conveyed.

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?

Given the tool's simplicity (4 params, 1 required, no output schema, no nested objects), the description covers the essential purpose, default behavior, and parameter examples. No obvious gaps.

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

Parameters4/5

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

Schema coverage is 100%, so baseline is 3. Description adds value by giving attribute examples (href, value, aria-label) beyond the schema's single example. This helps the agent understand what values to provide.

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?

Clearly states the action (read), resource (attribute of an element), and provides concrete examples (href, value, aria-label). This distinguishes it from siblings like 'get_value' or 'evaluate'.

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?

Implies usage for reading any attribute, but does not explicitly state when not to use or contrast with similar tools like 'get_value' or 'evaluate'. With many siblings, more guidance would improve decision-making.

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