steam_get_rarest_unlocks

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false, covering the safety profile. The description adds the 'unlocked' filter and the global unlock percentage sorting basis, but does not disclose additional behavioral traits such as default steamid behavior or error conditions.

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?

Single concise sentence, front-loaded with the key differentiator 'RAREST' and the sorting basis. No wasted words.

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?

The tool is simple and read-only, with comprehensive annotations and an output schema. The description adequately conveys the core purpose and enables correct tool selection, even without additional details.

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 tool description mentions no parameters. However, the input schema provides detailed descriptions for appid, limit, steamid, language, and response_format, effectively covering all parameter semantics. The description adds no extra meaning beyond the 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?

Description uses a specific verb ('Show') and resource ('player's RAREST unlocked achievements') plus the sorting criterion ('by global unlock %'). This clearly distinguishes it from sibling tools like steam_get_player_achievements (all achievements) and steam_get_global_achievement_percentages (global percentages).

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 clearly implies the tool's purpose: to list a player's rarest achieved unlocks rather than all achievements or global stats. However, it does not explicitly state when to use it over alternatives or provide exclusionary guidance.

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