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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description's only added behavioral fact is the "(1 credit)" cost, which is genuinely useful for budgeting; it says nothing about pagination behavior despite a cursor parameter, or about result shape.

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 short sentences with the action front-loaded and the cost appended as a parenthetical. Nothing is wasted, though the definition is so terse that it borders on under-specified rather than maximally efficient.

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?

With no output schema, the description should say something about what a search returns (video list, cursor for paging, per-page cost). It covers cost but leaves the return shape and pagination loop unexplained for a 4-parameter search 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 description coverage is 100% and both enum parameters are self-documenting, so the schema carries the full burden. The description adds no extra meaning such as how sort_by interacts with relevance or whether the cursor invalidates filters; 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?

The description gives a specific verb and resource ("Search TikTok videos") and adds the scoping phrase "by keyword," which implicitly separates it from siblings like tiktok_search_hashtag and tiktok_search_users. It never names those siblings explicitly, so an agent must infer the boundary, but the core purpose is unambiguous.

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?

Usage is only implied by the name and the "by keyword" phrasing; there is no explicit statement of when to pick this over tiktok_search_hashtag, tiktok_trending, or tiktok_video. The 1-credit note hints at cost-aware selection but is not framed as guidance.

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