audit_ios_a11y

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

Given the annotations already declare readOnlyHint=true and idempotentHint=true, the description adds behavioral value by enumerating exactly what is analyzed and how the input should be captured. It makes clear this tool consumes ready-made snapshot data and does not generate it, which is useful behavioral context beyond the safety 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?

The description is compact and well-structured: it opens with the action, then summarizes the audit checks, and closes with the exact input shape and capture mechanism. The inline list is a little long, but each part carries operational meaning and there is no filler or repetition.

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 nested complex schema with no output schema or param descriptions, the description covers the main input contract exceptionally well but leaves gaps: no description of return/output format, no explanation of the 'options.minTarget' field, and no units for colors or fields. These omissions leave an agent needing to guess some behavior despite the otherwise rich scaffold.

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 description explicitly lists the main required fields (elements, viewport, and the nested element attributes) and therefore gives useful semantics for the core parameters. However, the optional 'options' parameter and its 'minTarget' field are completely unexplained, and there are no descriptions inside the schema, so the tool doesn't provide complete parameter-level guidance.

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 clearly states the tool's operation: 'Score an accessibility-enriched iOS element snapshot' followed by the specific audits it performs (missing labels, tap target sizes, WCAG contrast, Dynamic Type clipping, VoiceOver order). This is specific enough to distinguish it from sibling audit tools such as audit_ios_screen or audit_contrast even without their 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 clearly indicates it should be used when an accessibility-enriched element snapshot is available and refers to the capture method ('via the AccessibilitySnapshot XCUITest / ios-capture harness'). It does not explicitly name alternative tools or state when not to use it, but the specific resource and capture requirement make the use case evident.

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