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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds ordering ('newest first') and cost behavior ('costs no credits'), which are traits the annotations do not convey.

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?

One compact sentence with the resource, ordering, returned fields, and cost all front-loaded; no filler and nothing that fails to earn its place.

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?

An output schema exists, so the description need not explain return values, and the credit-cost note plus ordering cover the key runtime concerns. The only gap is that it never distinguishes this tool from the near-identical 'first_videos' sibling.

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 the single 'limit' parameter is fully documented in the schema (default 12, max 50). The description adds nothing about pagination or the limit, so the 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?

States a specific verb and resource ('finished UGC videos') scoped to the user, with a clear sense of what the list contains. It does not, however, differentiate itself from the close sibling 'first_videos' or other list_* tools, so an agent still has to infer the boundary between them.

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?

There is no explicit when-to-use/when-not or named alternative, but 'Costs no credits' gives a real selection signal (prefer this over paid generation tools for cheap inspection). Usage is only implied rather than routed against siblings like get_video or first_videos.

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