extend_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 only states it creates a task and returns ids/status/URLs, but does not disclose important behavior such as it being asynchronous, the ability to poll (wait, poll_interval_ms), or webhook support. This is a significant gap for a task-creation tool.

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 a single concise sentence that front-loads the purpose and includes return value info. Every word earns its place, with no unnecessary fluff or repetition.

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?

The tool has 8 parameters, no output schema, and no annotations. The description explains the core purpose and return values, but lacks crucial context about async behavior, how to retrieve results (get_task), and the effect of the wait flag. This is incomplete for a complex task-creation tool.

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 75%, with most parameters already having clear descriptions. The description adds no additional parameter semantics beyond the context of 'extend video'. Since coverage is moderate and not low, a baseline of 3 is appropriate; the schema handles parameter documentation.

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 'Create a Grok Imagine task on RunAPI (extend video)', which is a specific verb+resource+scope. It distinguishes from siblings like text_to_video and image_to_video by explicitly saying 'extend video'. Also mentions it returns task id, status, and output URLs.

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 implies usage for extending an existing video via 'extend video', but it does not explicitly state when to use this tool vs alternatives or provide exclusions. There is no mention of prerequisites like needing a completed prior task, which is only in the schema. Thus, usage guidance is implied, not explicit.

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