Create a Game Center achievement

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

No annotations are provided, so the description carries the full burden. It discloses the side effect of creating an initial version and the return of the version ID, which is a key behavioral detail. However, it does not mention potential side effects like overcounting points or any rate limits, but for a creation tool, the description covers the essential behavior.

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 a single, concise sentence that front-loads the primary action and then provides a crucial secondary detail about the returned version ID. No wasted words; every clause adds value.

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?

For a creation tool with 6 fully documented parameters, no output schema, and a clear sibling workflow, the description is complete. It explains the return value (version ID) and how to use it, satisfying the agent's need to call the tool correctly and follow up.

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 the schema already documents each parameter. The description adds no parameter-level detail beyond what's in the schema, but it does mention the workflow context (version ID for localization) that is not in the schema. This is enough to meet the baseline of 3.

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 the tool creates a new Game Center achievement and additionally the initial version, returning its ID. It uses a specific verb ('Create') and resource ('Game Center achievement'), and it distinguishes itself from the sibling 'create_game_center_achievement_localization' by noting it returns the version ID for subsequent localization creation.

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 implies the intended workflow: after creating the achievement, the returned version ID is used to add localizations with the sibling tool. It does not explicitly state when not to use this tool or list preconditions, but the context of sibling tools and the schema (e.g., gameCenterDetailId from get_game_center_detail) provides clear usage context.

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