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

Annotations already declare read-only, non-destructive, idempotent behavior. The description adds value by specifying the per-relation match/mismatch/uncertain output and illustrating a typical drift case, with no contradictions.

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?

A single sentence packs purpose, relationship types, output semantics, and a motivating example without unnecessary filler. The em-dash example is illustrative and earns its place.

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?

The description covers the core contract: inputs (snapshots + checklist), behavior (comparison against named relationships), and outputs (per-relation match/mismatch/uncertain). It lacks an explicit return-value structure but is sufficient for an agent to invoke the tool correctly.

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?

With 0% schema description coverage, the description summarizes ios/android as {elements, viewport} and checklist as an array, and lists supported spatial relations. Still, it leaves checklist item 'a'/'b' reference semantics and tolerance behavior unexplained, requiring inference from schema field names.

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 names a specific comparison (iOS vs Android element snapshots) against a checklist of spatial relationships and explicitly mentions output categories (match/mismatch/uncertain). It clearly differentiates from sibling audit tools by focusing on cross-platform layout drift.

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 gives a concrete usage scenario (status text centered on one platform but top-aligned on the other) and states required inputs, making invocation conditions clear. However, it does not explicitly contrast with sibling tools like audit_consistency or audit_layout.

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