chesscom: Get player

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

Annotations already declare readOnlyHint, openWorldHint and idempotentHint, so the safety and idempotence profile is covered. The description adds the useful qualifier that the data is 'public', implying no authentication is needed for another user's profile, but says nothing about rate limiting, error behavior for unknown usernames, or whether a missing user returns an empty profile.

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 front-loaded sentence that puts the resource first and the return payload second; nothing redundant. The trailing 'etc.' slightly weakens it by leaving the return surface open-ended, which matters because there is no output schema.

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 no output schema, the description carries the burden of describing returns and does so adequately by enumerating the main profile fields. For a two-parameter, single-required, annotation-covered read tool that is close to sufficient, with the only real gap being how the optional 'fields' projection behaves.

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 parameters (username, fields) are already documented in the schema, which sets the baseline at 3. The description adds no syntax or behavioral detail about the comma-separated 'fields' projection filter, even though that is the one parameter whose semantics are non-obvious.

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 (Get), resource (Chess.com player) and scope (public profile), and enumerates the fields returned, so the agent knows this is a profile lookup rather than a stats or games query. However, it never names or contrasts with the close siblings that also take a username (chesscom_get_player_stats, chesscom_get_player_clubs, chesscom_get_player_archives, lichess_get_user), so differentiation is left to inference.

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?

No when-to-use or when-not-to-use guidance is given. The enumerated profile fields hint at scope, but nothing tells the agent to prefer chesscom_get_player_stats for ratings or chesscom_get_player_clubs for club membership, nor whether the call requires any setup. Structurally this matches the calibration MID example, which also scored 2.

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