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

With no annotations, the description carries the full burden. It does add real behavioral context: 'Free, no auth needed' and the lobby/match defaulting rule. It does not explicitly state the operation is read-only/safe or whether the returned snapshot is live vs cached, so it is adequate but not rich.

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 dense paragraph that front-loads the returned payload before the scoping/eligibility conditions. Nearly every clause carries information, though the parenthetical about match_id interrupts the return-field list.

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?

No output schema exists, so the description must describe returns – and it does list the key fields and the lobby countdown. It also covers auth ('no auth needed') and scope defaulting, making it largely complete for a zero-required-param read tool.

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 100%, so both api_key and lobby_id are already documented in the schema; baseline 3 applies. The description echoes the lobby_id default behavior and clarifies match_id as 'the permanent archive address', adding marginal meaning.

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 enumerates the specific fields returned (phase, tick, season, match_id, ticks per day, top-10 leaderboard) and their meaning, so the resource is concrete. However, the verb is implicit ('info') and it doesn't clearly distinguish itself from scoring_info, which likely also exposes the leaderboard.

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?

It explains scoping on multi-match servers (YOUR match when authenticated, else the passed lobby_id, else the main match), which is useful usage context. But there is no explicit guidance on when to prefer this over list_lobbies or scoring_info, leaving the selection to inference.

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