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

With no annotations, the description carries the behavioral burden and does so well: it discloses that page sizes vary, that boundary posts can repeat, and the exact cursor derivation logic. It does not address rate limits or auth, but for a read-only listing operation the disclosed quirks are the meaningful ones.

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?

Front-loaded with the core purpose, then the required input source, then pagination mechanics, then scope exclusions. Every sentence is functional; none is filler despite the density.

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?

No output schema exists, so the description appropriately previews the returned fields and explains pagination quirks, which is what an agent needs to page correctly. Minor gaps remain around error/empty-result behavior, but the coverage is strong for a listing tool.

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 100%, so the baseline is 3, but the description adds value beyond the schema by encoding the hasMorePrevious -> lastItem.createTime*1000 cursor rule and the 'omit cursor for first page' convention. It gives operational meaning to cursor and sec_uid rather than merely restating their types.

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 ('Get one native page of a creator's posts') and enumerates exactly what is returned (descriptions, timestamps, engagement stats, video and music data). The closing constraint 'No aggregation, ranking or per-video requests' cleanly disentangles it from search/popularity tools and video_detail.

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 clear when-to-use context: supply sec_uid from user_profile or video_detail, omit cursor for the first page, and follow the hasMorePrevious pagination rule. The exclusion of aggregation/ranking/per-video use is stated but the alternatives for those excluded needs are not named explicitly, so it stops short of a full 5.

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