pl_players_by_id

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=true. The description adds that auth is not needed, which is useful, and shows the exact return shape. But it doesn't disclose behavior like whether missing IDs are silently ignored, error handling, or rate limits. Given annotations cover the safety profile, a 3 is appropriate.

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 extremely concise: two sentences with a return format and auth note. Every line earns its place. The 'Returns:' line is front-loaded with the most critical information, followed by the simple auth disclaimer.

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?

Given this is a simple lookup tool with one parameter, no output schema, and strong annotations (readOnly, idempotent), the description covers the core semantics well. It could mention what happens with invalid/unknown IDs or the max batch size, but for a simple read-only batch lookup, the description is near-complete.

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?

The input schema provides 100% coverage: the only param 'id' is described as 'Player id(s)' with an example '[200785, 223094]'. The description adds context that this is a batch lookup and the expected return format. The schema is already quite clear, so the description adds marginal but useful value above the baseline.

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 clearly states 'Batch player lookup by a list of ids' with the specific use case 'hydrates lineups/squads', which distinguishes it from single-player lookups like pl_player or pl_player_basic. The return format is explicitly shown as a top-level array of objects with id, name, firstName, lastName.

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 implies when to use this tool: when you need to look up multiple players by IDs at once, especially to hydrate lineups/squads. However, it doesn't explicitly state when NOT to use it or mention alternatives like the single-player lookup tools (pl_player, pl_player_basic) for individual lookups.

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