generate_video

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

The description discloses that generation polls synchronously with a 10-minute timeout, and includes constraints like max video size (20 MB, .mp4, ≤8.7s) and duration limits (1–15 seconds). Since no annotations are provided, these details fully inform the agent about behavioral traits.

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 well-structured: an introductory sentence summarizing modes, a note on polling, then bullet-pointed Args and Returns. Every sentence adds value, and the most critical information (modes) is front-loaded.

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?

Given 11 parameters and no output schema or annotations, the description covers modes, parameter constraints, return format (Markdown block with URL, duration, cost), and polling behavior. Minor missing details include not explicitly stating that only one of image_path/image_url/video_path/video_url should be provided per call, though 'Only one mode per call' implies it.

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%, but the description compensates excellently with a detailed Args section explaining each parameter's purpose, constraints (e.g., max 20 MB, .mp4, ≤8.7s for video_path/video_url), and which parameters are ignored in edit mode.

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 'Generate or edit videos with Grok Imagine' and distinguishes between text-to-video, image-to-video, and video editing modes. It explicitly says 'Only one mode per call,' making the purpose specific and unambiguous.

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 clear guidance on when to use each mode (default text-to-video, provide image to animate, or source video to edit) and mentions reference images. However, it does not explicitly compare with sibling tools like extend_video or generate_image, nor does it state when not to use this tool.

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