search_books

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

No annotations are provided, and the description does not disclose behavioral details such as whether the tool is read-only, authentication requirements, rate limits, or any side effects. For a search tool, minimal transparency is given beyond the fact that it retrieves data.

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?

The description is extremely concise with only two sentences. The first sentence states the purpose, and the second provides a usage tip. No unnecessary information is included.

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?

Given the 5 parameters, no required fields, and no output schema, the description covers the main functionality and clarifies when to use keyword vs. specific fields. However, it lacks details about pagination, result format, or any limitations, which would improve completeness for a search 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?

The input schema has 100% description coverage, but the description adds value by explaining that the keyword parameter uses a different backend (BooksTotal) and suggests title/author/ISBN for book-specific searches. This context is not present in the schema.

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 the tool searches for books on Rakuten Books and lists supported search fields (title, author, ISBN). It distinguishes from a general keyword search but does not explicitly mention sibling tools like search_products or search_genres.

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 provides guidance on when to use the keyword parameter vs. specific fields, noting that keyword routes to a cross-category search. However, it does not contrast with other sibling tools or specify when to avoid this tool entirely.

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