Generate Video and Wait (Jimeng Video 3.0)

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

Annotations declare non-readonly, non-idempotent, open-world, non-destructive. The description adds genuinely useful behavior beyond that: the ~5 minute timeout, the 10-second polling interval, and critically the 1-hour URL validity. It does not say what happens on timeout beyond 'error message', which is a minor gap.

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?

Front-loaded purpose sentence, then composition, then behavior (timeout/interval), then args, then returns. Every line earns its place; no filler.

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?

Covers the wrapper relationship, polling behavior, timing, return value and URL expiry, and the cross-field requirement. For a blocking convenience tool with no output schema this is nearly complete; only timeout-failure handling is left implicit.

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 coverage is 100%, so baseline is 3. The description adds value by stating the frames mapping (121 for 5s, 241 for 10s) and the prompt's language/char limit, plus the crucial constraint 'Either image_url or image_base64 is required' – a cross-parameter rule JSON Schema cannot express.

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?

States a precise verb+resource ('Generate a video using Jimeng Video 3.0') and immediately explains this is a wrapper that combines the two named siblings. An agent can distinguish it from jimeng_generate_video and jimeng_query_video_task without opening any schema.

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?

Explicitly names both sibling tools it composes and describes the convenience-tool use case: submit-and-poll in one call. The timeout context ('video generation is slower than image generation') further signals when this synchronous wrapper is appropriate versus the async pair.

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