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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description's only extra behavioral detail is the 'newest first' result ordering, which is genuinely useful but leaves pagination and result limits undisclosed.

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, zero filler, with the scoping behavior front-loaded and examples immediately after. Every clause 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 read-only author lookup with full schema coverage and no output schema, the description plus annotations supply everything needed to call it correctly. Only result-size/pagination behavior is unaddressed, which is a minor gap.

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 'author' and 'country' are already documented in the schema, including the country enum list and its buy-link purpose. The description adds no parameter-level detail beyond that baseline.

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 states a specific verb and resource ('An author's books') and adds a scope qualifier ('newest first'), so the agent knows the ordering behavior up front. It doesn't explicitly contrast with siblings find_similar_books or get_book, but the resource is distinct enough to avoid confusion.

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 two example queries ('what has Andy Weir written?', 'Sally Rooney's books') give concrete trigger contexts that map directly to the tool's intent. There is no explicit when-not or named alternative, but the usage scenario is unambiguous for a lookup-by-author tool.

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