face_change_age

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

With no annotations provided, the description carries the full burden. It discloses the ability to both age and de-age, and that multiple faces can be processed. However, it lacks details on limitations (e.g., image requirements, result format, reversibility), which a typical agent would need for safe invocation.

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 sentence of 12 words, front-loaded with the core action. Every word earns its place; there is no redundancy or fluff. Ideal for quick scanning by an AI agent.

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 (2 parameters, output schema present), the description is adequate but incomplete. It does not clarify how the 'age_infos' array maps to multiple faces in the image, nor does it explain the return format or error cases. The presence of an output schema mitigates some gaps, but the description should still provide clarity on usage flow.

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 coverage is 100% with clear parameter descriptions (e.g., 'URL of the portrait' and 'Target age information for each face'). The description adds the nuance of 'Age or de-age' and 'one or more faces', but these are already inferable from the schema. The added value is modest, warranting a baseline 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 action ('Age or de-age') and resource ('faces'), and specifies scope ('one or more'). It effectively distinguishes from sibling tools like 'face_change_gender' and 'face_cartoonize' by focusing on age transformation.

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 explicit guidance on when to use this tool vs. alternatives. While the description implies usage for age transformation, it does not mention when not to use it (e.g., for gender changes) or provide context about prerequisites, making it unhelpful for decision-making among siblings.

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