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

Annotations already declare destructiveHint=true, openWorldHint=true, and idempotentHint=false, covering the safety profile. The description adds that this submits an asynchronous Builder task, but omits what happens to prior data, whether auth/keys are required, or how results are retrieved. Some added context but several gaps remain.

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 sentences, front-loaded with trigger conditions followed by the task/collector detail. The keyword enumeration is somewhat verbose, but nothing is wasted and the structure is easy to parse.

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 an 8-parameter, task-submitting tool with no output schema, the description covers the trigger and collector but does not explain the task lifecycle — whether it returns a task ID, how long it runs, or how the agent retrieves results via siblings like scraper_task_status/scraper_task_result. Adequate but incomplete.

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 eight parameters (bitrate, kilohertz, audio_format, subtitles fields, etc.) are already documented. The description adds no parameter-level meaning beyond the schema; the 'youtube_audio_by-url' collector identifier is not a parameter. Baseline 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?

The description states a concrete action — submitting a YouTube audio collection Builder task with a fixed collector identifier (youtube_audio_by-url) — which is specific and actionable. It distinguishes the resource (audio files) from the many scraper siblings, though it never explicitly contrasts against neighbors like youtube_video or youtube_transcript.

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 provides trigger conditions (user wants YouTube audio combined with verbs like collect/scrape/download), which gives implied usage context. However, it names no alternatives and gives no when-not guidance, leaving the agent to infer why this tool over youtube_video or youtube_transcript.

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