capcut_add_video

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

With no annotations provided, the description carries the burden of behavior disclosure. It reveals the crucial non-persistent session edit behavior, which is valuable. But it omits other side effects, such as whether existing clips are replaced or how the new clip interacts with the timeline's current content.

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 two concise sentences: the first states the core purpose, the second provides the essential persistence caveat. Every word earns its place, with no filler or redundancy.

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?

For a tool with 14 parameters, no output schema, and no annotations, the description is too thin. It omits important context such as expected return values, how the clip behaves relative to existing timeline segments, and the meaning of the many optional transform properties. The session/save note is helpful but insufficient for complete guidance.

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 only 36%, and the description adds no parameter information. Many parameters like file, posX, scale, speed, volume, opacity, rotation, draft, and trackRenderIndex have no guidance in either the schema or the description, leaving the agent to guess their meaning.

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 tool adds a video clip to a track, using a specific verb and resource. It also differentiates from sibling tools like capcut_add_image, capcut_add_audio, and capcut_add_track by specifying 'video clip' and 'on a track'.

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 workflow context by noting this is a session edit and to call capcut_save to persist. However, it does not explicitly state when to use this tool versus alternatives like capcut_add_image or capcut_add_audio, nor does it mention any exclusions or prerequisites.

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