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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true), and the description adds the meaningful cost trait '1 point per call', which is real behavioral information. It says nothing about what happens with more than 20 titles, an unsupported language code, partial failures, or output ordering – gaps that matter for a billed, non-idempotent call.

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?

It is two clauses long and front-loads the action and the use case. The '(1 point per call)' parenthetical duplicates the title verbatim and carries no new information in the body.

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 3-parameter tool with no output schema, the description leaves the return shape (e.g. aligned array of translated strings vs a single blob) unexplained, and it does not address behavior past the 20-title ceiling or invalid language codes. It is workable but not complete for an agent that must handle results programmatically.

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 titles, language, and idempotency_key are all documented in the schema itself. The description only echoes the <=20 limit already stated in the titles schema and says nothing extra about language formats or how a returned translation maps back to input order; baseline 3 applies.

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 ('Translate up to 20 news titles into one language') and adds a concrete motivation ('before showing headlines to a user who reads another language') that makes it unambiguous against read-oriented siblings like get_news or get_news_article.

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 supplies a clear when-to-use scenario (presenting headlines to a reader of another language) and implicitly scopes the call to title-sized text rather than full articles. It stops short of any exclusion guidance, e.g. what to do for bodies longer than a title or when to prefer fetching the article instead.

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