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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the bar is lower. The description still adds real value beyond them: result ordering ('most matches first'), the 'last team' field returned, and an explicit cost ('Costs 1 credit') that the agent cannot get from the schema or annotations.

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 sentence that front-loads the primary use case and then the secondary mode, with no filler. Every clause (name forms, ordering, team_id path, credit cost) carries information an agent needs.

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?

With an output schema and rich annotations present, the description need not explain return values, and it still summarizes them ('most matches first and their last team'). Cost and both query modes are covered; only the meaning of the limit parameter is left unexplained.

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 75% and the league default plus team_id provenance ('from list_teams') are documented in the schema. The description adds meaning beyond it by spelling out the accepted name formats, but it says nothing about the limit parameter, which has bounds in the schema yet no explanation of its effect.

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 states two concrete capabilities with specific verbs and resources: resolve a player name to an id, and list a team's players via team_id. It also names the accepted name forms (scorecard short form "V Kohli" or full name), which distinguishes it from get_player, which plainly expects an id.

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?

Usage is clearly framed by intent: 'Use to find a player's id by name' or 'list a team's players with team_id', which tells the agent which of the two modes to pick. It does not explicitly say when to prefer it over siblings like get_player or get_player_stats, so it falls short of full alternative routing.

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