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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description still adds real value beyond that: the shape of the payload (base/expansion flag, notes, family links, card types with physical dimensions and quantities) and the explicit empty-list behavior for games with no card sets, which prevents an agent from misreading a valid empty result as failure.

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?

Three sentences, front-loaded with the action, then payload contents, then the empty-result edge case. The middle sentence is a long enumerated run-on, but every element is informative and nothing is filler.

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 single-parameter read tool with an output schema and readOnly annotations, the description covers purpose, typical use case, payload composition, and the empty-result edge case. An agent has everything needed to call it confidently; the return-value detail is mildly redundant with the output schema but not harmful.

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 100% and the single parameter is already documented in the schema as a required positive game id. The description adds no formatting or validity detail beyond that, so the schema does all the work and the baseline 3 applies.

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 names a specific verb and resource (list a game's card sets) and scopes it to a single game id, which distinguishes it from broad siblings like boardgamegeek_game or boardgamegeek_entity. The only blemish is the awkward 'Get List' phrasing, but the intent is unambiguous.

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?

'Useful for card-size or sleeving questions' gives an implied use case, which is more than nothing. However, it never says when to prefer this over a general game lookup, nor any prerequisites or exclusions, leaving routing to inference.

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