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

Annotations mark it readOnly/openWorld, and the description adds real behavioral value by enumerating the possible status values (processing/published/failed) and explaining that privacyStatus reflects what YouTube actually applied, i.e. it may differ from what was requested.

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; the identification instruction comes first and the return-value semantics second, with no filler.

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 no output schema, the description covers the meaningful return fields (status, privacyStatus), so an agent knows what comes back. The only shortfall is the unexplained accountId/profileId parameters.

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 0% and three parameters exist, so the description must compensate. It successfully explains videoId as the publishId from create_post but says nothing about accountId or profileId, leaving a genuine gap.

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 ('Check a YouTube upload by its videoId'), and clarifies scope by pointing at the create_post publishId, which separates it from sibling insight tools like get_youtube_video_insights.

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?

Gives a clear triggering context — call it after create_post to inspect the returned publishId — but does not explicitly state when not to use it or name a competing alternative.

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