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

Beyond the annotations, it discloses credit spending, price parity with prismposter.com, several-minute runtime, approval-required behavior with nothing running until answered, library saving, and refusal rules for minors/public figures before charge. This is unusually rich behavioral context for a non-read-only generation tool.

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?

The purpose is front-loaded in the first sentence, and the remaining sentences pack in prerequisites, pricing, approval, saving, and refusal rules without filler. Every sentence adds operational value.

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 complex, credit-spending generation tool with no output schema, it covers prerequisites, pricing, approval, refusals, runtime, and saving. Its main gap is that it does not describe the successful return value or explicitly tell the agent to poll get_job for the result.

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 the schema already documents all four parameters, but the description adds meaningful track_id context by requiring a kept song or an edit_song-derived source. It also reinforces the approval_id flow, though it says nothing extra about idempotency_key beyond the schema.

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?

It states a specific verb and resource: make a full-length music video for a whole song, with generated scenes cut to the music from start to end. The scope contrast with lyric videos and generic video tools is implicit but clear enough from 'full-length music video' and 'generated scenes cut to the music'.

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 explicitly says to use a kept song made here, and to remix or extend the person's own audio with edit_song first. It also names quote_job for pricing and explains the approval_required path when the person must decide something first.

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