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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered; the description adds useful behavioral context by noting the data is credential-free and sourced from AniList and that entries are normalized. No contradiction with 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?

Front-loaded with purpose, then data provenance, return shape, and parameter defaults in a tight sequence. The return-field enumeration is slightly redundant given an output schema exists, but overall it earns its length.

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 paginated search with an output schema and full parameter coverage, the description covers purpose, source, pagination clamps, and routing. The only gap is that the sort parameter's allowed values are never surfaced, though the schema carries them.

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 description coverage is 100%, so page, per_page, query and sort are already documented. The description merely restates the page and per_page defaults and omits the sort ordering options entirely, adding little beyond the schema – baseline 3.

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 and resource ('Searches anime by free-text query') and names the sibling it is not ('Use anime_title to get an anime'), so an agent can separate this list-search tool from the detail tool without opening schemas.

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?

Names the alternative anime_title explicitly and the condition that selects it, giving clear routing guidance. It does not mention other related siblings such as anime_rankings or anime_airing_schedule, so it stops short of full when/when-not coverage.

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