price_deck

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

With no annotations supplied, the description carries the burden and does reasonably well: it discloses the pricing rule (cheapest in-stock printing), the input tolerance (three list formats, blank lines and // comments ignored), and the caveat that results differ from pre-built deck carts. It omits what happens to cards with no in-stock printing and any error behavior, which keeps it from 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 is front-loaded in one sentence, followed by a scoping caveat and a compact Args block. The three inline format examples earn their place by removing parsing ambiguity, though the prose repeats the list-format idea slightly across sentences.

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 not required, and the description covers input format, pricing basis, and the comparison caveat. The main residual gap is how unpriced or out-of-stock lines are reported, which matters for a pricing tool but is arguably visible in the output schema.

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%, so the description must compensate, and it does: it defines decklist as newline-separated with concrete examples and ignored-line rules, and explains that commander is optional and 'priced and reported separately.' That is meaningful semantics well beyond the bare string types in the schema.

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 opens with a specific verb and resource: 'Price a decklist against ManaPool's live singles inventory.' It also distinguishes the result from ManaPool's pre-built deck cart totals, which separates it from the deck-oriented siblings (get_deck, search_decks, audit_deck). It stops short of explicitly naming a sibling tool it should be preferred over, so it lands at 4 rather than 5.

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?

'Use this to budget a custom build' gives a clear positive use case, and the note about pre-built decks using a single seller's stock tells the agent when this estimate differs from other totals. There is no explicit when-not-to-use guidance or named alternative (e.g. use get_card for a single card), so it is clear context without exclusions.

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