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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds value beyond that: it states the data source is POKEKA market data only, that server-side request logging is disclosed in the privacy policy, and that it does not modify user data. Rate-guarding of whole-set sweeps is mentioned but primarily lives in the schema, so this falls just short of 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?

The core purpose and return contents are front-loaded, and the routing guidance follows logically. However, the bilingual duplication of the statistics list adds length without new information for a primarily-English reader, slightly diluting density.

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 needn't be spelled out, and annotations cover the safety profile. The description supplies usage triggers, alternatives, data-source scope, and privacy disclosure, making it essentially complete for correct invocation. Minor remaining gap is no explicit mention of what happens when a set_code matches nothing.

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 all three parameters already carry their own documented semantics (lang track, pagination limits, accepted set_code formats). The description's note about accepting internal set_code, official abbreviation, or set name largely restates the schema's set_code description, adding little new meaning. 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 a specific verb+resource (whole-set statistics for one Pokémon TCG set) and enumerates exactly what is returned: total cards, per-language-track counts, rarity breakdown, variant breakdown, top featured Pokémon, plus a paginated checklist. It explicitly distinguishes itself from siblings by naming set_top_priced_cards and card_price as the tools for price-related questions.

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?

Provides an explicit when-to-use trigger ("Use for questions like 'how many cards / SR cards are in 151c'") and exclusions: catalog data only, redirecting pricing questions to set_top_priced_cards and card_price. The alternative-routing is unambiguous.

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