Test Layout

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, but it only lists what areas the tool inspects. It does not state whether the operation is read-only, how results are returned, whether a browser/page must already be open, or any side effects.

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 compact and front-loaded: the layout concerns appear first, then the widths parameter details. It is terse to the point of being skeletal, but it wastes no words.

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?

Despite having an output schema, the description is not complete enough for reliable invocation: the required target parameter is undefined, and the relationship to sibling tools is unstated. An agent would have to guess what to pass as target and when to prefer this over full_qa.

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?

Schema description coverage is 0%, so the description must compensate. It usefully explains widths (screen widths in px, with defaults), but says nothing about the required target parameter or max_pages, leaving the most important inputs ambiguous.

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 identifies the resource (layout) and enumerates specific checks it performs: text overlap, truncated text, horizontal scroll, contrast, small tap targets. This gives an agent a concrete sense of what the tool covers, though it never states an explicit verb like 'tests' and doesn't name sibling tools to forestall confusion with full_qa or test_fonts.

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?

There is no guidance on when to choose this tool over siblings such as full_qa, test_fonts, or test_interactions. The listed layout issues imply a use case, but the description leaves the selection decision entirely to the agent.

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