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

Annotations already declare readOnly and openWorld, so safety is covered. The description contributes the credit cost, which is genuinely useful operational context, but says nothing about behavior for private, suspended, or nonexistent accounts — the most likely failure modes.

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?

A single compact sentence that front-loads the resource and then the payload. No filler; the parenthetical credit note is placed last where it belongs.

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 one-parameter read tool with no output schema, listing the returned fields is the right move and largely suffices. Missing is any note on error/empty behavior or on response shape (nested vs flat), which an agent calling with an arbitrary handle would want.

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% and the schema already explains the handle format ('with or without @'), so the description adds nothing on parameters. 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?

Names the resource (TikTok profile) and enumerates the exact fields returned (bio, avatar, followers, following, likes, video count), which distinguishes it from siblings like tiktok_profile_videos or tiktok_followers. The implicit verb is retrieval; a clearer 'Get' would push it to a 5.

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?

No statement of when to use this versus tiktok_search_users (to find a handle), tiktok_followers/following (which return the underlying lists behind the counts), or profile tools for other networks. The agent must infer selection 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.