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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety bar is covered. The description adds useful context — desktop browser scope, single-attribute read semantics, and example attributes including data-* — but does not cover failure modes when the element or attribute is absent. Credit for adding platform and scope context beyond the annotations.

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 compact sentences: the first front-loads purpose and scope, the second handles sibling routing. Every clause earns its place with no redundancy.

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 read-only tool with full annotation coverage and 100% schema description coverage, the definition is nearly complete; no output schema means return format need not be explained. The only minor gap is not stating behavior when the element or attribute is missing.

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 100%, so the schema already documents pageId, selector, and attribute. The description adds 'data-*, anything' beyond the schema's example list and reinforces the pageId scope, but provides no syntax, format, or edge-case detail. Baseline 3 is appropriate.

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?

States a specific verb ('Read'), resource ('one attribute of an element'), and scope ('DESKTOP grid browser (by pageId)'), and explicitly distinguishes itself from the sibling webpage_get_attribute. An agent can identify the exact operation without opening the schema.

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 explicitly routes platform choice: 'for a phone or tablet use webpage_get_attribute.' The condition that selects the alternative is stated, leaving nothing to inference for the main sibling.

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