getBoxModel

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

No annotations are provided, so the description must carry the burden. The verb 'Get' implies a read-only operation, and the description lists the categories of data returned. However, it does not disclose error behavior, return format, or any side-effect potential, which is a gap but not a contradiction.

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

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

The description is a single, concise sentence that is front-loaded with the primary action and resource, followed by a colon-separated list of the included properties. There is no redundant wording, making it highly efficient.

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

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

For a simple single-parameter tool with no output schema, the description adequately conveys the return categories (dimensions, positioning, margins, padding, borders). It could be more explicit about the return structure (e.g., units or coordinate system), but overall it is sufficiently complete for an agent to understand the tool's basic function.

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

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

The input schema has 100% coverage (selector described as 'CSS selector'), so the baseline is 3. The description adds no additional meaning beyond the schema, but it does imply that the selector refers to an element from which the box model is obtained.

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

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

The description clearly states the tool's purpose with a specific verb ('Get') and resource ('element box model'), and enumerates the contained data (dimensions, positioning, margins, padding, borders). This is more specific than a generic 'get element info' and differentiates from siblings like getComputedCss, though it does not explicitly mention alternatives.

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

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

The description provides no guidance on when to use this tool versus alternatives like getComputedCss or getElementDetails. There are no stated scenarios, exclusions, or prerequisites, leaving the agent to infer usage from the name and description alone.

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