Get a user's statistics

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

Annotations already indicate readOnlyHint and openWorldHint. The description adds critical behavioral context beyond annotations, warning that stats aggregation can lag and may return all-zero for active accounts, instructing agents not to misinterpret such results. This is a valuable caveat not derivable from annotations.

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 three sentences, front-loaded with purpose, and each sentence provides value. Slightly dense with multiple clauses, but no fluff. The 'confirmed live' anecdote is a bit wordy but reinforces the caveat.

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 an output schema present, return values are covered. The description addresses purpose, exact parameter usage, data freshness caveats, cross-checking guidance, and alternatives. For a single-parameter read-only tool with these quirks, this is complete.

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% (the 'user' parameter is documented as ID or username). The description adds useful semantic nuance: it must be an exact username, no need to search first, and partial/fuzzy names require search_user. This helps the agent use the parameter correctly beyond schema.

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's function: 'Get an AniList user's anime/manga statistics' and lists specific data fields (counts, mean score, time watched, episodes/chapters/volumes consumed). It also distinguishes from siblings by explicitly mentioning no need for search_user and directing to get_full_user_info for profiles.

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 gives explicit when-to-use and when-not-to-use guidance: 'no need to call search_user first unless you only have a partial/fuzzy name' and 'Use get_full_user_info instead of also calling get_user_profile separately.' It also advises cross-checking get_user_list if results are zeroed.

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