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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It only mentions 'Searches for movies' but does not disclose any specifics about output format, pagination, rate limits, authentication, or any side effects. For a search tool, this is minimally transparent.

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 short and front-loaded, with the core purpose in the first sentence. The additional metadata (Group, Billing) is tangentially useful but does not inflate the text unnecessarily. It is concise and scannable.

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 tool has 8 parameters and no output schema, the description is insufficient to understand the tool's full behavior. It does not explain how parameter combinations work, the meaning of 'movies' (e.g., does it filter by category?), or what the returned results look like. The schema covers parameters but the description lacks an integrative overview.

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%, with each parameter having its own description in the schema. The tool description adds no additional meaning or clarification beyond what the schema already provides, so it stays at the baseline of 3.

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 states a specific verb and resource: 'Searches for movies on YouTube.' This clearly distinguishes it from sibling tools like get_youtube_v3_search_video (general videos) and get_youtube_v3_search_channel (channels). The purpose is unambiguous and not a tautology.

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 guidance is provided on when to use this tool versus alternatives. It simply states the action without mentioning use cases, exclusions, or comparisons to the generic search or other search-type tools. The name implies the scope but the description adds no explicit direction.

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