Set an item's star/favorite level

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

No annotations are present, so the description carries the full behavioral burden. It adds a valuable nuance: the star is a 3-level rating, not a plain on/off flag, which goes beyond the schema's enum. However, it omits other behavioral details such as auth requirements, idempotency, or side effects.

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, front-loaded sentence with no filler. Every word contributes to explaining the tool's purpose and the star scale, making it concise and well-structured.

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 mutation tool with three required parameters, no annotations, and no output schema, the description is too minimal. It lacks explanations for the ID parameters, return behavior, and prerequisites, leaving an agent with insufficient context to use it reliably.

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 0%, and the description only explains the 'star' parameter's values (0=unstarred, 1=favorite, up to 3). It does not explain the roles of categoryId and itemId, nor how they identify the item placement, leaving a significant gap for an agent to invoke the tool correctly.

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's action ('Sets the star level') and resource ('this item placement'), and explicitly defines the value scale (0-3). This distinguishes it from sibling item update tools like set_item_quantity or set_item_worn.

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 provides no guidance on when to use this tool versus alternatives. It does not mention prerequisites, exclusions, or why one would choose set_item_star over other item update tools. The only implied use is setting a star, but there is no explicit usage context.

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