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

Annotations already establish that this is read-only, idempotent, open-world, and non-destructive, so the description only needs to add value beyond those flags. It does by warning that public game data is untrusted and that wins do not guarantee claims, which is a meaningful behavioral caveat.

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 two short sentences with no filler. The first sentence enumerates the exact contents of the result, and the second provides a non-obvious caveat. Every part earns its place.

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 simple read-only list tool with an output schema and strong annotations, the description is largely complete: it identifies what is returned and warns about data trust. The only clear gap is that limit behavior is not mentioned, but the single optional bounded parameter and output schema keep this minor.

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?

There is only one optional parameter, limit, but schema description coverage is 0% and the description does not explain how limit affects results. The field name is somewhat self-evident, but a one-line clarification such as 'limits the number of returned lobby entries' would be needed to compensate.

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 explicitly states the verb and resource: it lists Arcade games, tool routes, waiting NFHs, and verified weekly winners. This clearly distinguishes it from sibling tools such as join_arcade_game, play_arcade_move, and get_arcade_match, which suggest different operations.

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 no explicit guidance on when to use this tool instead of alternatives. There is no mention of when to list the lobby versus joining a game, playing a move, or fetching match details, so the agent must infer usage context.

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