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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds meaningful context beyond that: the credit cost ('Costs 1 credit') and a concrete inventory of returned fields, which is valuable given there is no output schema.

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 efficient sentences with the resource stated first and field details following; the redundant 'Profile.' opener is minor waste but the rest earns 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?

Without an output schema, listing returned fields is a strong completeness win, and the credit cost is disclosed. However, the undocumented cache_max_age parameter and absence of any handle-format or usage context leave gaps for a tool with two parameters.

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 only 50% — 'cache_max_age' is undocumented in both schema and description — and the description says nothing about the parameters at all. With a coverage gap, the description needed to compensate for the undocumented parameter but does not.

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 names a specific resource (public Kwai profile) and enumerates exactly the fields returned (followers, following, video count, likes, bio, avatar, category). This distinguishes it clearly from siblings like kwai_post or kwai_userPosts, though the leading lone word 'Profile' is redundant.

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 guidance on when to use this tool versus kwai_userPosts, kwai_post, or profile-style siblings on other platforms, nor any prerequisites or exclusions. The agent must infer usage from the field list alone.

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