Favorite asset character

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

Annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=true, idempotentHint=false, openWorldHint=true). The description adds only the scope of the user's fal Assets library, without elaborating on reversibility, effects, or the idempotency key behavior. With annotations covering the safety profile, a 3 is appropriate.

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 with no wasted words. It is concise and easy to parse, though very sparse for a tool operating in a dense sibling environment.

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?

Annotations cover the safety profile and the schema covers all parameters, so the core mechanics are clear. However, the lack of sibling differentiation and when-to-use guidance leaves a routing gap for an agent with many similar tools.

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 all four parameters are fully documented in the schema. The description adds no parameter-level meaning beyond what the schema already provides, making the baseline 3 correct.

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 and resource ('Favorite an asset character') and scopes it to the authenticated user's fal Assets library. It does not distinguish this tool from siblings like favorite_asset or favorite_asset_collection, so it lacks the differentiation needed for a 5.

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 gives no guidance on when to use this tool versus the many sibling favorites tools (favorite_asset, favorite_asset_collection, unfavorite_asset_character). It also does not mention the 'confirm' parameter's condition, which is only explained in the schema.

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