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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds useful behavioral context about the return payload (model names, modes, enums, ranges, defaults) and that it is a prerequisite step for the create_* tools, though it says nothing about size of the catalog or whether results are cached/live.

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?

Two tight sentences, zero filler, with the what (full model catalog) front-loaded and the when (before the create_* calls) immediately after.

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?

No output schema exists, yet the description explains what an agent receives (models with modes and exact input fields) and why it matters (building `inputs`). For a read-only one-parameter list tool, nothing needed to call it correctly is missing.

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% and the single `category` enum is fully documented in the schema. The description's 'video, image and motion-control' wording loosely mirrors the enum values but adds no filtering syntax or behavior beyond what the schema already gives; baseline 3 applies.

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 resource (video, image and motion-control models) and what each entry carries (modes, exact input fields, enums, ranges, defaults). It is clearly distinguished from the create_* siblings it feeds, which it names explicitly.

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?

Gives an explicit when-to-call rule: 'Call this before create_video / create_image / create_motion_control to pick a model and build `inputs`.' The alternatives and the ordering constraint are both stated, leaving nothing to inference.

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