zen_bounds

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

Annotations are missing, so the description bears full responsibility. It correctly describes the output (bounding rect and viewport/page sizes) but does not mention any side effects, permissions, or constraints. For a read-only operation, this is acceptable but minimal.

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?

Single, front-loaded sentence with no wasted words. Efficiently conveys the core functionality.

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 tool with two parameters and no output schema, the description is adequate but incomplete. It omits return format, potential errors, and edge cases like missing elements.

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 coverage is 0% with no parameter descriptions. The tool description adds no meaning to 'selector' or 'tab_id' beyond the schema; it does not explain what the selector refers to or how tab_id is used.

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?

Description clearly states the tool returns getBoundingClientRect plus viewport/page sizes for an element, using a specific verb and resource. This distinguishes it from sibling DOM tools like zen_dom or zen_html.

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?

No guidance on when to use this tool versus alternatives such as zen_dom or zen_computed_style. The description does not specify any conditions or exclusions.

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