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

Annotations declare a non-read-only, open-world, non-destructive operation; the description usefully adds the external AI dependency and the image-source inputs. However, it omits that this is an expensive, long-running generation job whose result must be fetched via get_video_generation_status — a material behavior for an openWorldHint=true tool. No cost, latency, or failure-mode context.

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?

Three sentences, front-loaded with the capability then the trigger then the prerequisites — no filler. Slightly dense with parentheticals, but every clause carries operational information.

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?

Output schema exists so return values needn't be explained, and the required exercise_id plus image source precondition are covered. But for a 9-parameter, long-running generation tool, the description leaves the async lifecycle and half the parameters unaddressed, which is not enough for confident standalone invocation.

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%, so the description must carry all nine params. It explains trainer_image_url (HTTP URL or data:image base64), trainer_image_id (sourced from Workout Defaults), and user_requirements in effect, but leaves team_id, equipment, exercise_type, target_muscles, and exercise_description entirely unexplained in both schema and description.

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 ("Generates an AI exercise video from a trainer photo") and names the underlying service (CloneMotion). The framing "create exercise videos without filming" tells an agent exactly what unique capability this tool owns versus the many list/create workout siblings.

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?

Provides an explicit trigger condition ("Use when the user wants to create exercise videos without filming") and concrete preconditions (have the target exercise and an image source before calling). It does not name the follow-up sibling get_video_generation_status, so the agent must infer that generation is asynchronous and needs polling.

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