YouTube Video API

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

No annotations are provided, so the description must carry the full burden. It only says 'Get details and metadata' without disclosing what fields are returned, error behavior, rate limits, or any special requirements. This leaves the tool's behavior as a black box.

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 a single, front-loaded sentence that conveys the essential purpose with no filler or redundant information.

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 simple, low-complexity tool, the description plus well-documented schema is minimally viable. However, the absence of an output schema or any mention of return values means the agent cannot know what 'details and metadata' actually includes.

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?

The input schema has 100% coverage with descriptive parameter explanations (e.g., v as 'YouTube video id', country as ISO code, language as code), and the description adds no extra parameter context. Baseline 3 is appropriate since schema does the heavy lifting.

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 'Get details and metadata for a single YouTube video' uses a specific verb and resource, clearly distinguishing this tool from siblings like youtube_search, youtube_transcripts, and youtube_channel by focusing on a single video's metadata.

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 when a known video ID is available and details are needed, providing clear context. However, it does not explicitly state when not to use it or mention alternative tools for search, transcripts, or channel info.

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