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

Annotations already state readOnlyHint=true, destructiveHint=false, idempotentHint=true. The description adds that it fetches data from MyAnimeList via Jikan and returns specific fields. It does not disclose additional behavioral traits like rate limits or error handling, but annotations cover safety and idempotency, making the description adequate.

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 a single, front-loaded sentence that efficiently conveys the tool's purpose and key details without unnecessary words. It is concise and well-structured.

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?

The tool has one parameter with complete schema coverage, an output schema exists (so return values need no explanation), and the description fully explains what data is returned. No gaps are present.

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% coverage for the single parameter 'id', with a clear description. The tool's description adds minimal additional meaning beyond the schema's description of the parameter, so it meets the baseline but does not exceed it.

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 retrieves character cast and Japanese voice actors for an anime, specifying data types (names, roles, images) and source (MyAnimeList via Jikan). This distinctly differentiates it from sibling tools like anime.titles.details (general details) and anime.titles.search (search by title).

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 implicitly indicates when to use this tool (for character/voice actor information) but does not explicitly state when not to use it or mention alternatives. However, the context provided is sufficient for an agent to select the correct tool among siblings.

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