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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the safety profile is clear. The description adds valuable behavioral context: it explicitly states that absence of FACEIT data results in an error message, not silent omission. This is beyond the annotations and helps the agent understand error handling.

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 concise (two sentences) and front-loaded with the key purpose. The first sentence is slightly dense with parentheses, but it remains efficient and avoids unnecessary detail.

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 the tool's simplicity (1 parameter, no output schema, rich annotations), the description covers the essential behavior: what data is returned, error handling, and the explicit nature of missing accounts. It is complete enough for an agent to use correctly.

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 has 100% description coverage, fully detailing the 'id' parameter with multiple SteamID formats. The description adds no additional parameter-specific meaning beyond what the schema provides. Baseline score of 3 is appropriate.

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 it returns a FACEIT player object with specific fields (nickname, country, per-game skill level, ELO) plus bans. It also clarifies behavior when no account exists. However, it does not explicitly differentiate from sibling tools like steam_profile or steam_bans, which could also return player or ban data.

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 guidance is provided on when to use this tool vs. alternatives such as steam_bans, steam_profile, or steam_identity. The description only mentions error handling for missing accounts, which is helpful but does not help the agent decide between tools.

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