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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds non-obvious behavior: omitting `season` silently returns the current season, and a `moreRows` signal requires a follow-up call with a larger `limit` capped at 60. The `moreRows` mention is slightly ambiguous since it is a response field, not a parameter, but the retry instruction is actionable.

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 front-loaded sentences: what it returns, when to call it, then parameter guidance. No filler. The pagination sentence is slightly awkward in referencing `moreRows` without saying where it appears.

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, no-output-schema lookup with fully documented params, the description covers the returned row shape, the evidenceId grounding, default season behavior, and the pagination loop. An agent has everything needed to call it and to interpret a truncated result.

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%, so baseline is 3, but the description adds real semantics the schema lacks: the consequence of omitting `season` (current season) and the pagination escalation rule up to 60 rows. It does not address `asked` or `includeAllSeasons`, though the schema documents those adequately.

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?

States a specific verb and resource plus the exact row shape (one row per player with an evidenceId, name, NTRP rating, wins, losses, matches, Desk level), which is far more than the title alone. It does not name or contrast against near-neighbors like query_club_teams or query_team_record, so an agent must infer the distinction.

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?

Gives a clear trigger ('when someone asks who is on a team, or before you state a fact about a roster') and a conditional rule for `season`. It stops short of explicit when-not-to-use guidance or naming an alternative tool for related roster-adjacent questions.

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