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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=true), so the description's job is to add payload and cost context — and it does, disclosing the full composition of the response and the frames sampling window with its default. The credit cost of the clips option lives in the schema rather than the description, and nothing is said about failure behavior or result size, which keeps it below a 5.

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 a single sentence, front-loaded with purpose and then a comma-delimited payload inventory, which is efficient for a tool with no output schema. The enumeration is long but every item is informative; only the trailing parenthetical feels slightly tacked on.

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?

With no output schema and a three-parameter surface, the description carries the burden of telling the agent what comes back, and it does so field by field, including the shot count and sample-frame spread. Combined with the schema's clips cost note, an agent has enough to decide and call correctly; only error behavior is unaddressed, which is minor.

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 67% and the one undocumented parameter, frames, is exactly the one the description rescues by stating the 0–24 range, the default of 6, and that frames are spread across the title. The title parameter's slug-or-name flexibility is already in the schema, and clips is fully described there, so the description adds meaning but mostly fills a single gap.

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 precise verb-and-resource statement ("One anime series or film in depth, by slug or name") and then enumerates the payload: synopsis, credits, characters, genres, themes, trailer, indexed-shot count, similar titles, and sample frames. That enumeration distinguishes it cleanly from find_animation_titles (search), find_similar, and get_animation_sequence without the agent needing to open any schema.

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 implies the tool is for retrieving a single known title by slug or name, and the parenthetical about frames gives a default, which nudges usage. However, it never states when to prefer this over find_animation_titles for discovery or over find_similar for lookalikes, and it doesn't mention what happens when the title isn't found. Usage is inferable but not spelled out.

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