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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds real context beyond that: the cost ('Free'), the enumerated state space (queued, rendering, done, failed), and the conditional return of the video link only when done. It still omits what happens for an unknown or expired job_id.

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?

Two short sentences, front-loaded with the cost signal and then the return value. Nothing is padded and no sentence fails to carry information.

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?

With no output schema, the description carries the return-value burden and does so by stating the state values and the conditional link. The remaining gap is the provenance of job_id, which matters for a tool whose entire input is an opaque identifier.

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?

The single job_id parameter has 0% schema description coverage and the description does not say where the identifier comes from, what format it takes, or whether it is reusable. With one undocumented parameter, the description should have compensated and does not.

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 names a specific resource (a music-video job) and what is returned (its state, plus the video link when done), which is enough to separate it from the generation siblings like vngrd_bassline or vngrd_cover_art. The verb is implied rather than stated, which keeps it just short of a 5.

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?

There is no explicit when-to-use guidance, no mention that job_id comes from one of the sibling generation tools, and no advice on polling after submission. The only usage signal is the leading 'Free', which implies it is safe to call casually but does not route the agent.

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