edit_video

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

No annotations are provided, so the description carries the full burden. It discloses the 8.7-second maximum length and the fact that the edited video has the same duration as the original, which are useful behavioral details. However, it omits the model parameter caveat (grok-imagine-video-1.5 does not support editing) and does not describe error handling or processing behavior, leaving significant gaps.

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 three sentences long, each adding value: it states the purpose, gives a usage instruction, and lists key constraints. It is front-loaded with the core action and contains no fluff 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 6 parameters, no annotations, and no output schema, the description covers the essential behavior (editing existing video), key constraints (8.7s max, same duration), and offers a usage hint. However, it does not mention the model caveat or the exclusive-or relationship between video_url, video_path, and video_file_id, though these are present in the schema. It is fairly complete but not exhaustive.

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 100%, so the baseline is 3. The description does not add much beyond the schema; it mentions providing a 'source video URL along with a prompt,' but the schema already documents all parameters and their constraints, including the mutually exclusive video source fields and the 8.7-second limit. The description adds no new parameter semantics.

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 function: 'Edit an existing video' using the xAI Grok Imagine Video API. It also specifies key constraints (max 8.7 seconds, same output duration) that distinguish it from sibling tools like generate_video and extend_video, which create or extend videos rather than edit them.

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 establishes a clear context: it is for editing an existing video. This implicitly differentiates it from siblings that generate, extend, or upload videos. However, it does not explicitly state when not to use this tool or name alternative tools, so it lacks explicit exclusion criteria.

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