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

Annotations already indicate a destructive, non-read-only action. The description adds meaningful side effects: contacting the provider, storing the dub, replacing the project asset reference, and potentially refunding the original charge. No contradiction with annotations.

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?

Three concise sentences, front-loaded with the core purpose and followed by the important side effects and output behavior. No filler or redundant wording.

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?

The description covers the important output states and the post-completion videoUrl behavior, and explains both completion and failure side effects. It is complete enough for an agent to invoke the tool, though it does not describe the exact response shape.

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 low at 33%: only dubbingId has a description and it is minimal. The tool description does not meaningfully explain projectId or targetLang, and does not compensate for the missing parameter documentation.

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 specific action (poll and finalize) and resource (a language-dub job), enumerates completion/failure behavior, and explicitly says it does not start a new dub, which distinguishes it from dub_video.

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 implies this tool is used after a dub has started and clarifies it will not start a new one. However, it does not explicitly name the alternative tool or state additional conditions such as 'do not use if you need to create a dub.'

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