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

Beyond the read-only annotations, the description discloses per-item success/error granularity, duplicate preservation behavior, input-order handling, and a specific credit cost per successful entry. These are meaningful behavioral traits an agent could not infer from the schema or annotations alone.

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?

The description is two sentences with no filler. The core behavior, count range, result style, duplicate handling, and cost are all front-loaded clearly and economically.

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?

Given low complexity, one required parameter, existing output schema, and safe read-only annotations, the description covers the essential behavioral context. The only notable gap is the lack of a pointer to the singular `get_tiktok_video` tool for single-item retrieval, which would round out the context.

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 0%, so the description carries some burden. It does add semantics by noting that input order is preserved and duplicates are distinct, and it implies the content of the `urls` array. However, it does not explicitly describe the parameter name, value form, or URL type expectations beyond the schema definitions.

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 clearly states a specific verb ('Fetch'), a resource ('TikTok video URLs'), and a bounded count ('1–20'), making the batch purpose evident. It does not explicitly contrast itself with the singular sibling `get_tiktok_video`, so it slightly misses full sibling differentiation.

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?

The description implies usage for batch-fetching TikTok video URLs, and the input-order/dedup details suggest a batch-processing use case. However, it never explicitly says when to prefer this tool over `get_tiktok_video` or other TikTok tools, nor does it mention any exclusions.

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