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

With no annotations, the description carries the full burden. It usefully discloses that the result is a NEW asset (non-destructive) and that the track can optionally be repointed, which are real behavioral traits. However, it omits whether the operation is long-running/async, whether it costs credits, and what happens to the source media.

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?

A single front-loaded sentence that names the action, the result, and the optional side effect with no filler. Every clause earns its place.

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 mutation/generation tool with no annotations and no output schema, the description is adequate but incomplete: it explains the create-plus-optional-track behavior yet says nothing about the return value, async nature, or failure modes an agent would need to invoke it confidently.

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 100%, so all six parameters (including modelId, voiceId, voiceReferenceUrl) are already documented in the schema. The description adds no format, constraint, or dependency detail beyond what the schema provides, so the baseline of 3 applies.

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 specific verb (create) and resource (a new voice-changed version of an audio media item), and clarifies the operation is additive rather than an in-place edit. It implicitly distinguishes itself from the change_video_voice sibling by scoping to audio, but never names that alternative.

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?

No when-to-use guidance, no prerequisites, and no mention of the near-identical change_video_voice sibling or when to prefer generate_audio_track. The only usage hint is the optional track-repointing behavior, which is about mechanics, not selection.

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