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

The annotations already establish this is a safe, idempotent, non-destructive read (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false). With that baseline covered, the description earns credit for disclosing the response content — placement, event, price to build, cards, and paste-ready decklist text — which is valuable given there is no output schema. It doesn't add auth, error, or missing-id behavior, so it stops 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?

A single front-loaded sentence: the primary action and the id, then the parenthetical payload list and id provenance. No filler, nothing repeated from the schema or annotations.

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 read-only lookup with no output schema, the description adequately covers the return contents and the default behavior of the optional price source is carried by the schema. Error handling for an unknown id is the only notable omission, which is minor for this tool class.

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 coverage is 50%: the `source` enum is documented in the schema, but `deckId` has no schema description. The description compensates by telling the agent where valid ids come from (get_archetype, buildable_meta_decks), which is semantic context the schema lacks. It still says nothing about id format or invalid-id behavior, so it is not fully compensating.

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?

Specific verb+resource: it retrieves a full tournament decklist by id, and enumerates the payload contents (placement, event, price to build, cards, paste-ready text). It also names the sibling tools that produce valid ids (get_archetype, buildable_meta_decks), so the agent can distinguish it from get_card, get_archetype and save_deck without opening any 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?

The parenthetical routes the agent to get_archetype and buildable_meta_decks as the id sources, which is genuine usage guidance for the required parameter. There is no explicit when-not or alternative retrieval path, but the intended workflow is unambiguous.

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