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

Annotations already cover read-only, idempotent, closed-world safety. The description adds real context the annotations don't: accepted transliterations (Armenian, Russian, Latin) and a defined no-query fallback returning top authors by book count, which is the main branch an agent must anticipate.

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 tightly packed sentences: the primary lookup first, the zero-parameter behavior second. No filler, no restatement of the title.

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?

Covers both call modes (with and without query) for a two-parameter tool, and the schema handles pagination, so no output schema is needed. Minor gaps: result ordering for query searches and whether matching is case- or diacritic-sensitive.

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 coverage is 100%, so baseline is 3, but the description adds meaning beyond the schema's 'Part of the author's name' by noting that partial matching works across three scripts. Pagination in the schema is self-explanatory and needs no restatement.

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?

States a specific verb+resource (find authors) plus the matching dimension (name), and it distinguishes itself implicitly from get_author by describing lookup by partial name. It does not explicitly name sibling tools, but the purpose is unmistakable.

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?

It gives a clear usage rule: use with a query for name lookup, omit the query to get the most prolific authors. It lacks an explicit contrast with get_author (exact/ID lookup), so an agent must infer that boundary.

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