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

Annotations already indicate this is a mutating operation (readOnlyHint false). The description adds no behavioral context such as the need for polling, which is a key parameter (polling default true). No discussion of execution time, failure modes, 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 padded with marketing phrases ('captivating videos,' 'advanced AI technology') and ends with an incomplete 'Use cases:' line. It is not front-loaded and does not communicate the essential function efficiently.

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?

Despite having an output schema and nested request object, the description never explains how to construct a request, what the required parameters are, or what to expect in the response. It is more of a product blurb than an API tool description.

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?

The schema has meaningful descriptions for nested parameters like prompt and dst_duration, but the tool description itself does not mention any parameters. With 50% schema coverage, the description fails to clarify usage or provide context for the un-documented parameters.

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 says 'transforms text prompts and images into captivating videos,' which mixes text and image inputs. This blurs the distinction from the sibling 'AI-Video-Generator-Image-to-Video' and does not clearly state that this is specifically a text-to-video tool. The name indicates text-to-video, but the description adds conflicting image-generating instructions.

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 an image-based workflow ('start with a photo that features a clean background... upload your image'), which is not the intended text-to-video use case. It gives no guidance on when to prefer this tool over the image-to-video sibling or other AI video tools.

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