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

Annotations already cover the safety profile (readOnly=false, destructive=false, idempotent=false, openWorld=true). The description adds genuinely useful context beyond them: that this enqueues an asynchronous job and that the original sound is preserved unless a new prompt is supplied, clarifying it is non-destructive.

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 tight sentences with the core action front-loaded and the async nature stated immediately after. The trailing 'POST /music/edit operation remix' is terse endpoint jargon but still carries information without bloat.

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 100% schema coverage and annotations covering the safety profile, a 6-param mutation tool is mostly covered; the async-job disclosure is the key missing piece the description supplies. It does not state what the enqueued job returns (e.g., a job id for flowmusic_get_job), which is a minor residual gap given no output schema.

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 every parameter (clip id format, seed, model enum, title, lyrics tagging, prompt override) is already documented in the schema. The description mentions lyrics and the optional sound prompt but adds no format or constraint detail beyond that baseline.

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 and resource: re-sing a clip with edited lyrics, optionally overriding the sound prompt. An agent can distinguish it from flowmusic_write_lyrics and flowmusic_replace_section by the 're-sing the whole clip' framing, but no sibling is named to remove ambiguity.

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 never says when to choose this over flowmusic_write_lyrics, flowmusic_cover_song, or flowmusic_replace_section, nor what preconditions (a finished clip) are required. 'A job' hints at the async workflow but is not usage guidance.

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