get_card_prices

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

No annotations are provided, so the description carries the full behavioral burden. It discloses that no currency conversion happens (a meaningful behavioral trait) and names the exact currencies/markets. However, it doesn't disclose whether this is a read-only operation, rate limit concerns, or what happens for cards without prices in one market. The description adds some genuine behavioral context beyond the name.

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 a single efficient sentence with zero wasted words. It packs market names, currencies, and the absence of conversion into a compact statement that's easy to parse. Could arguably add more, but at the sentence level it's well-structured and front-loaded with the core purpose.

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?

Has an output schema which reduces the burden of describing return values. With 2 params and moderate tool complexity, the description covers the core purpose but leaves out key details: what set_code does, behavior when one market has no data, and when to prefer this over compare_card_prices or get_set_prices. It's adequate for a simple lookup but has clear gaps for effective selection among closely-related siblings.

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 0%, meaning the schema provides no descriptions for card_id or set_code. The description only mentions 'TCGPlayer USD and CardMarket EUR variants' but doesn't explain what set_code does or how it modifies the query (whether it's optional scoping or required in some cases). The description fails to compensate for the low schema coverage, leaving param semantics unclear.

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 clear verb+resource ('Get' + 'card prices') and specifies the markets (TCGPlayer USD, CardMarket EUR), with a note about no currency conversion. It distinguishes from siblings like compare_card_prices and get_set_prices by its scope (single card, two specific markets). However, it doesn't fully distinguish from get_card_price_history or summarize_card_value, so it's clear but not fully differentiated.

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 implies when to use this tool (when you need raw USD/EUR prices without conversion) but provides no explicit when/when-not guidance or named alternatives. There's no exclusions or reference to sibling tools like compare_card_prices or get_set_prices. The usage context is implied rather than stated.

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