Get prices for a Pokémon card

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

Description adds substantial behavior beyond annotations: rows for all printings come back together with a warning to inspect each row, basis distinguishes GUIDE from DERIVED, PTCG_INDEX is explained, and data is delayed by at least a day. Annotations only declare readOnly/openWorld/idempotent, so this rich behavioral detail is valuable and consistent.

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 longer than average but each sentence earns its place: it front-loads the core purpose, then necessary caveats about printings, basis, and data delay. No filler or repetition.

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?

Given that there is no output schema, the description thoroughly explains the return structure and semantics: field meanings, multiple-rows behavior, indexing, and time delay. An agent can correctly interpret and use the result without missing critical context.

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 the schema already documents id and currency well. The description goes further by clarifying that no currency conversion happens and that results are denominated per the currency parameter, plus contextualizing output fields like basis and PTCG_INDEX, which aids parameter interpretation.

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 states a specific verb and resource: it returns every current price observation for one card, enumerating the fields (source, basis, printing, grade, sample size, day). It clearly scopes to a single card, which distinguishes it from sibling tools like ptcg_search_cards or ptcg_get_cards.

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 clear context: use this to fetch all price observations for a single card. It does not explicitly name alternatives or state when not to use it, but the card-level scope and the price-specific semantics make the use case evident.

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