apple_list_analytics_report_instances

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

No annotations are provided, so the description carries the full burden. 'List' implies a read-only operation, but nothing is said about result size, pagination, whether instances expire, or how granularity affects the returned instances – all relevant for a report-instance listing.

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 short sentence with no filler, front-loaded with the verb. It is efficient, though the terseness is part of why other dimensions are underspecified.

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 3-parameter reporting tool with no annotations and no output schema, the description should say what an instance is, how granularity changes results, and where to go next (segments/download). Almost none of that is present.

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 only 33% (only processingDate is documented, as YYYY-MM-DD). The description adds no meaning for reportId, granularity (DAILY/WEEKLY/MONTHLY), or how filtering by processingDate interacts with the instance-per-date model, leaving real ambiguity for two of three parameters.

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 the verb and resource ('List generated instances ... of an analytics report') and adds a useful clarifying gloss ('one per processing date'). However, it does not distinguish this from close siblings such as apple_list_analytics_reports, apple_list_analytics_report_requests, or apple_list_analytics_report_segments, so an agent could plausibly confuse the four.

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 when-to-use or when-not-to-use guidance, and no mention of the sibling tools that retrieve related analytics artifacts. The agent must infer the sequencing (request -> reports -> instances -> segments -> download) entirely from tool names.

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