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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The only behavioral addition is the "newest first" ordering, which is useful but also just a restatement of the title; nothing about result size, pagination, or edge cases (e.g., ambiguous author names) is disclosed.

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 sentences, front-loaded with the core behavior, with no filler. It loses a point only because the first sentence duplicates the title verbatim rather than spending those words on new 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?

For a simple two-parameter lookup with no output schema, the description states what is returned (the author's books) and how they are ordered, which is adequate. It omits what a book entry contains and how ambiguous or missing authors are handled, leaving minor gaps.

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 100%, so both the author and country parameters are already documented (including the country enum values in the schema) and the baseline of 3 applies. The description adds no syntax, format, or disambiguation detail for parameters beyond what the schema provides.

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?

Names the resource (an author's books) and its ordering (newest first), and the quoted example requests make the intent unmistakable. It never names or contrasts with its siblings (find_similar_books, get_book), so it falls short of the 5-level sibling differentiation.

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?

"For requests like 'what has Andy Weir written?'" gives an implicit trigger for use, which is more than nothing. However, there is no guidance on when to prefer this over get_book or find_similar_books, and no exclusions or prerequisites.

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