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

Annotations only declare readOnlyHint and openWorldHint; the description adds genuinely new context: an auth prerequisite (configured signer) and a billing cost (1 credit). It stops short of describing failure behavior when the signer is unconfigured or what a returned playlist record contains.

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?

Short, front-loaded, and each sentence carries a distinct fact (identity, jargon, workflow, prerequisite, cost). The first two sentences overlap slightly in restating the resource, but the jargon clarification 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?

For a read-only paginated list tool with no output schema, it covers the essentials: what is listed, the pagination partner, auth requirement, and cost. Remaining gaps (return shape per playlist, the undocumented cache parameter) are minor.

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 75%, with `handle` (formats), `count` (default/max) and `cursor` well documented; only `cache_max_age` is bare. The description adds nothing about parameters, so the schema does essentially all the work — the baseline 3 fits.

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 resource (a creator's playlists) and even disambiguates TikTok's jargon, noting playlists are called "mixes". It clearly separates itself from the follow-on `tiktok.playlistVideos`, though it doesn't distinguish from other adjacent siblings like `tiktok_collectionVideos` or `tiktok_userShowcase`.

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?

"Pair with `tiktok.playlistVideos` to walk one" gives an explicit workflow step and names the alternative/complement. Prerequisites ("Requires a configured TikTok signer") and cost are stated, but there is no explicit when-not-to-use guidance versus collection or showcase tools.

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