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

Annotations already declare readOnly, idempotent, and closed-world, so safety is covered; the description adds the hard 10-row return cap, the exact fields returned, and the sort dimension set. It does not mention pagination or what happens when a fuzzy query matches nothing, which is the main remaining behavioral gap.

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 workflow, then return shape, then a concrete example — a logical order. The return-field sentence partly duplicates the output schema, and the trailing example is useful but slightly redundant with the parameter list.

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 12-parameter read tool with an output schema and full annotations, the description covers purpose, workflow routing, return cap, and the key filter/sort semantics. An agent has everything needed to call it correctly on the first try.

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?

With 67% schema coverage, the description still adds value by naming the filter categories (set, number, rarity, condition, variant, game, price) and translating the sort enum into prose ('relevance, price, recency, or 7-day price change'). The price filters' cent units and response_format are left to the schema, which documents them, so the residual gap is small.

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 ('Search the BinderDex Pokemon and One Piece card catalog') plus the matching mode (fuzzy name) and the full filter surface. An agent can distinguish it from binderdex_browse_sets or binderdex_get_market_movers without opening the 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?

Explicitly sequences the workflow: 'Use this first to find a card's id, then pass that id to binderdex_get_card or binderdex_get_price_history,' naming the sibling tools that follow. It also gives a conditional rule ('Pass game ... when the user names a specific game'), so both the entry point and the alternative path are spelled out.

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