Top Titles By User Ratings

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

With no annotations provided, the description carries a heavier burden. It adds useful behavioral context: no join means no title-matching loss, and the results represent a small user panel rather than the books table. It does not disclose behavior around defaults, ranking construction, or how min_ratings affects the population, though the schema and output schema partially cover usage.

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?

Three short sentences with the purpose front-loaded and no filler. The additional sentences earn their place by clarifying data-source limits and warning that this is a small panel rather than general book ratings.

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 description, combined with fully documented parameters and an output schema, is sufficient for an agent to select and invoke the tool correctly. A slightly more explicit mention of sibling routing would improve completeness, but the user-panel vs books-table distinction already covers the main confusion risk.

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 documents all four parameters with 100% coverage, including direction values and a caveat for min_ratings. The description adds no parameter-level semantics, but the baseline of 3 applies because the schema already carries the meaning.

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?

First sentence states a specific verb ('Best- or worst-liked titles') and a specific resource ('4,154 users in user_ratings'). It also draws a clear contrast with the books table, which distinguishes it from the sibling tool top_books_by_rating and lets an agent identify a unique purpose.

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 states scope and an exclusion: 'Stays entirely inside user_ratings -- no join' and 'not the books table'. This gives clear context for when this tool applies, but it does not explicitly name sibling alternatives or give a direct when-not-to-use rule, so it falls just short of the strongest routing guidance.

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