book_lists

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

With no annotations provided, the description carries the full disclosure burden and largely succeeds: it reveals sorting behavior ('ordered by popularity'), return composition (title, total member votes, book count, url), and a hard constraint ('limit capped at 40'). It does not cover error behavior or auth needs, but for a simple read-oriented list tool these are minor omissions.

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 short paragraphs with zero wasted words. The core purpose is front-loaded in the first sentence, and the second paragraph packs return fields, use cases, and the limit cap into three sentences — every sentence earns its place.

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 simple two-parameter tool with an output schema available, the description covers purpose, ordering, output shape, use cases, and the limit constraint. Since an output schema exists, return values needn't be spelled out further. The only notable gap is absence of sibling routing guidance, which is not critical given the clear scope statement.

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 0%, so the description must compensate. It adds real meaning for limit ('capped at 40') and implies book_id's role via 'a book appears on', but book_id is never explicitly documented and no format or edge-case behavior is given. Partial compensation rather than full.

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 and resource: 'List the Listopia lists a book appears on', clarified by a concrete example ('Best Dystopian Fiction'). This clearly distinguishes the tool from siblings like similar_books, get_book, or get_shelf — an agent can tell at a glance what resource is being queried and how it differs.

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 gives explicit use-case context: 'Good for "what kind of book is this / what's it grouped with" and for discovery.' This tells the agent when the tool is valuable, though it stops short of naming alternatives or stating when not to use it, e.g., versus similar_books.

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