Listing statistics

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

Annotations already declare readOnlyHint, idempotentHint, etc. Description confirms 'Read-only analytics' and adds operational limits (200 listings, 270 days) not in annotations. 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?

Two sentences: first defines purpose and metrics, second provides usage guidance and limits. No wasted words, front-loaded with key information.

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?

No output schema, so return values are not required. Description covers purpose, all parameters (via schema), limitations, and sibling differentiation. Missing explicit pagination or response format, but acceptable for a read-only stats 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 coverage is 100% (all 6 parameters described). Description adds context like 'calls are not supported here' and 'group by day/week/month', but most info is already in schema. 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 clearly states it returns counters (shallow statistics) for listings over a period, listing specific metrics (unique views, contacts, favorites). It distinguishes from siblings by naming alternative tools for extended analytics and calls.

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?

Explicitly states when to use this tool vs alternatives: for specific item_id metrics grouped by time; for extended analytics use items_post_item_analytics; for calls use items_post_calls_stats. Also includes limits (200 listings, 270 days) as usage constraints.

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