dom_snapshot

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

With no annotations, the description effectively conveys the tool's read-only nature and output contents. It could mention error handling (e.g., if ref is invalid), but the core behavioral traits are clear.

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?

Two sentences with no redundant words. First sentence states output, second gives precise usage guidance—maximally 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 tool with one parameter and no output schema, the description covers purpose, output types, and usage boundaries. It doesn't detail subtree depth or error responses, but the context is sufficient.

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 single parameter 'ref' is explained in schema; description adds value by linking ref to view_page's refs, aiding cross-tool consistency. Schema coverage is 100%, elevating baseline from 3 to a 4.

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?

Clearly states it provides structured layout data (bounding boxes, computed styles, paint order, colors) and distinguishes from siblings view_page and capture_image, making the purpose explicit and unique.

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?

Openly states when to use ('spatial questions view_page cannot answer') and when not to ('for element discovery or text: use view_page; for visual verification: use capture_image'), providing explicit alternatives.

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