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

Annotations already declare readOnly/openWorld=false/destructive=false, and the description adds genuinely new behavior: the dataset size and time span, the active-only default with automatic fallback and self-reporting, and a cost signal ('Costs 2 credits'). These are traits an agent could not derive from the structured fields.

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 use case, then scope, then fallback behavior, then cost and the downstream handoff. No filler and nothing repeated from the title.

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?

An output schema exists, so return shape needn't be explained, and the description supplies the remaining decision-critical facts: search scope, fallback logic, credit cost, and the id handoff to get_player_stats. Nothing an agent needs to call this correctly is missing.

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 all five parameters (query, team, limit, active, position) are already documented, including the fallback semantics of 'active'. The description restates the default/fallback behavior but adds no syntax or format detail beyond the schema, matching the baseline for a fully-covered schema.

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+resource ('find a player by name, partial match') and immediately scopes the corpus ('~25,000 players back to 1999'). It also differentiates itself from the sibling get_player_stats by declaring that its output (the GSIS player id) is what that tool requires.

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 clear entry context ('Use to find a player by name') and a downstream routing hint ('Returns the GSIS player id needed by get_player_stats'), which tells the agent where this fits in a chain. It does not state when *not* to use it (e.g. versus get_player_leaders or get_player_stats directly), so it falls short of full alternative coverage.

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