Music task status

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

Beyond the annotations (which only declare idempotent/non-destructive/non-open-world), the description discloses valuable behavior: the call blocks up to waitSec, returns a public URL on 'completed' or the same 'processing' status otherwise, and credits are charged only when the track is ready with failures free. It omits whether a file is written locally when outputDir is supplied, which matters given readOnlyHint=false.

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?

Three short sentences, front-loaded with the purpose and the gating condition, then the wait semantics, then the billing rule. No redundant restatement of the name or title.

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 4-parameter, no-output-schema tool, the description is largely self-sufficient: it explains the return value (public URL vs 'processing') that the missing output schema would otherwise cover, and it explains billing and blocking semantics. The remaining gap is the file-download side effect of filename/outputDir.

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 only 25% (only outputDir is documented in the schema), so the description must compensate. It does add real meaning for waitSec ('Waits up to `waitSec`') and implies taskId comes from vivid_generate_music, but it says nothing about `filename` or the download-to-disk behavior behind `outputDir`.

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 states a specific verb and resource ('Get the track of a vivid_generate_music call') and scopes the input to a task that previously returned 'processing', which lets an agent distinguish this from a generic job poller like vivid_job_status without opening either 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?

It clearly states the triggering condition (a vivid_generate_music call that returned 'processing') and what the wait does, but never names vivid_job_status or vivid_list_jobs as alternatives, so the agent must infer when to prefer this specialized poller over generic job status tools.

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