listing__get_screenshots

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is known. The description adds behavioral context beyond that: it reveals the one-step nature and exactly what information is returned (locales, device sizes, counts, dimensions), and it explains the efficiency rationale. It does not go into pagination or error cases, but the presence of an output schema lowers that burden.

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 deliver the core purpose, the output scope, the required input, and an explicit comparison to a more expensive alternative. Every clause earns its place—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?

The tool’s complexity is moderate, but the description covers the key purpose, the output highlights, and the recommended usage context. Since an output schema exists, the description does not need to spell out return fields, and the efficiency warning about chaining calls is valuable contextual guidance.

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 input schema has 100% description coverage, with clear descriptions for app, locale, and version. The description’s mention of 'Give the app' and the 'one step' optimization does not add meaningful parameter semantics beyond what the schema already provides, so the 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?

The description opens with a specific verb ('List') and a clear resource ('screenshots on an app’s store listing'), then enumerates what the result includes (locales, device sizes, counts, dimensions). It also distinguishes itself from the manual multi-call chain (app_store_versions / localizations / screenshot_sets / screenshots), making the tool's purpose unmistakable.

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?

It explicitly says 'Use this instead of chaining app_store_versions / localizations / screenshot_sets / screenshots' and explains why (most locales carry no screenshots, so the chain is costly). It also tells the caller what input to provide ('Give the app (name, bundle ID or Apple ID)'), leaving no ambiguity about when to invoke this tool.

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