app_previews_create_instance

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

No annotations are provided, so the description carries the full burden, and it discloses almost nothing. 'POST' implies a mutation, but there is no mention of auth requirements, whether a preview set relationship is mandatory, what gets created, or irreversibility — all critical for a write operation on a nested JSON:API body.

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?

It is short and front-loaded, but the endpoint is stated twice redundantly ('POST /v1/appPreviews (POST /v1/appPreviews)'), and brevity here reflects under-specification rather than efficient communication.

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?

With no annotations, no output schema, and a free-form nested body object, the description should explain the JSON:API envelope requirements and required relationships. Instead it only defers to an external OpenAPI schema an agent may not have access to, leaving the definition materially incomplete for a mutation tool.

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% and there is a single body parameter whose schema already points to components.schemas.AppPreviewCreateRequest, so the schema does the heavy lifting. The description's pointer to the same OpenAPI schema adds no meaning beyond what the parameter definition already states.

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 only restates the HTTP method and path ('POST /v1/appPreviews') — essentially a tautology of the tool name rather than a statement of what an app preview is or what creating one accomplishes. It gives no domain-level distinction from siblings such as app_preview_sets_create_instance or app_previews_update_instance.

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?

There is no guidance on when to use this tool, what prerequisites exist, or how it differs from the many sibling create_instance tools in the App Store Connect surface. Nothing routes the agent between this and app_preview_sets_create_instance.

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