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

With no annotations, the description carries the full burden. It clearly implies a read-only data-fetch operation and enumerates the specific data returned (caption, counts, URLs, cover images, music info, author details). It does not mention error cases like invalid IDs or what happens if both parameters are provided, but the core behavior is well disclosed.

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, front-loaded with the primary purpose, and every detail serves a purpose. No fluff or redundancy.

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 the absence of an output schema, the description thoroughly covers return values by listing the data categories. It also addresses the parameter exclusivity and relates to a sibling tool. This is complete for a single-video lookup 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 coverage is 100%, so the schema already describes both parameters well. The description adds the crucial constraint 'Provide exactly one of url or video_id' and notes that video_id is 'as returned by search_tiktok', enriching the semantic meaning beyond the raw schema.

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 the tool gets full details for a single TikTok video, with specific verb and resource. It distinguishes itself from sibling tools like search_tiktok and tiktok_user_profile by focusing on single-video detail retrieval.

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?

It explicitly instructs the agent to provide exactly one of url or video_id, which is key usage guidance. However, it doesn't explicitly name alternative tools for search or user profile cases, relying instead on the tool's clear single-video scope.

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