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

With no annotations, the description carries the full behavioral burden and discloses useful traits: it is free, returns the clip URL on success, and failed renders refund themselves. It does not mention authentication, rate limits, or whether repeated polling is safe, but it covers key cost and outcome behavior.

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 tightly written sentences with the core purpose front-loaded. 'Free' is a terse but valuable cost signal, and the success/failure behavior is stated compactly without waste.

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 simple one-parameter polling tool with no annotations and no output schema, the description covers purpose, cost, success return, and failure refund. It could better explain the pending state or response shape, but the word 'Poll' implies repeated calls and the core behavior is clear.

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% and already explains that the id is 'returned by generate_video.' The description adds only 'by id,' so it does not meaningfully extend parameter semantics beyond the schema. 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?

States a specific verb+resource: 'Poll an async video job by id.' The resource 'video job' clearly distinguishes it from sibling status tools like get_image_status and get_music_status. An agent can identify its function without opening the 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?

The word 'Poll' implies repeated calls and the schema parameter description ties the id to generate_video, giving implied usage context. However, the description does not explicitly state when to use this tool versus alternatives or when not to use it, leaving the agent to infer the workflow.

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