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

Annotations already declare readOnlyHint=true and a human title, so the safety profile is covered. The description adds genuinely new behavior: 'One immediate snapshot, never loop' tells the agent not to poll, which is not in any structured field. It does not describe the shape of the returned status payload, which would be the remaining gap.

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?

Purpose is front-loaded, but the description is dense with repeated routing heuristics and repeats the media-type phrase twice ('VOICE-OVER / narration / dialog / spoken TTS clip'). Most sentences earn their place as disambiguation, yet the same message (this is the dialog status tool) is restated three times.

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 read-only status tool with no output schema, the description covers selection, alternatives, and the no-loop behavior, which is what an agent needs to call it correctly. It never explains what the status response actually contains (progress, URL, error states), which is the one remaining unknown.

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 50%: inline_media is fully documented in the schema, but placeholder_id has no description. The description compensates partially by stating that placeholder_id can be either an id or a 'var2 link', which is useful beyond the schema. With the other half of the meaning carried by the schema, a baseline 3 is appropriate.

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 first sentence names a specific verb+resource: a status check for a voice-over/narration/dialog/TTS clip. It explicitly distinguishes itself from siblings by media type ('Is the voice-over done?' → THIS tool, never var2_get_video_result or var2_get_audio_result). An agent can route without opening any other schema.

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?

Explicit when-to-use triggers ('Is it ready / done yet?', 'check on it', status question with an id/link), explicit when-NOT-to-use (action verbs like 'animate it'/'upscale' go to the matching create/modify tool), and the correct sibling pair (var2_create_dialog). It also states the routing rule for the ambiguous case (pick by media word).

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