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

Annotations already cover read-only, idempotent, non-destructive behavior, so the description only needs to add context. It does: set_id switches the tool from a list to a detail response that embeds the top 10 highest-value cards, which is a meaningful behavioral disclosure not in the annotations. It stops short of noting the list cap of 25 or default 15 in prose, but the schema covers that.

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?

Three sentences, front-loaded with the primary list mode before the set_id override and the sibling pointer. Slightly dense with parenthetical asides, but every sentence carries routing or scope information.

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?

An output schema exists, so return-value explanation is unnecessary, and the description already flags the notable embedded '10 highest-value cards' payload. Both operating modes, the filter options, and the sibling alternative are covered — nothing an agent needs in order to call it correctly is missing.

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 parameters are already fully documented, including the game enum values and the set_id mode switch. The description largely restates those facts ('filterable by series/query and by game') rather than adding new semantics such as matching rules or id formats. 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?

States specific verbs and resources: lists Pokemon and One Piece sets, and with set_id returns a single set's detail plus its 10 highest-value cards. The dual mode is stated up front and the tool is clearly differentiated from binderdex_search_cards and binderdex_get_card.

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?

Gives concrete question archetypes ('what sets exist', 'most valuable card in [set]') that map to each mode, and explicitly names binderdex_search_cards as the alternative for individual cards. An agent can route without opening any schema.

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