youtube_trending

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

With no annotations provided, the description carries the entire burden of behavioral disclosure. It reveals a quota cost ('Costs 1 quota unit') but fails to state whether the operation is read-only, what the return structure looks like, or whether authentication is required. The absence of these details limits the agent's ability to anticipate side effects or response handling.

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 extremely concise: one purpose sentence, one quota note, and three parameter lines. It front-loads the most essential information (what the tool does) and uses a clean, scannable list format for arguments. Every line earns its place.

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 lack of an output schema, the description should explain what the returned data contains. It does not mention the output format, fields, or pagination behavior. While parameters are well-covered, the overall utility is diminished because the agent cannot predict the response structure, which is critical for such a data-returning 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?

The description adds full meaning to each parameter beyond the schema: region_code is defined with ISO example, category_id includes a concrete example ('28' for Science & Technology), and max_results includes an explicit maximum (50). This compensates completely for the 0% schema description coverage.

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 begins with 'Get currently trending videos on YouTube', which is a specific verb+resource combination. This clearly distinguishes the tool from siblings like youtube_search (searching) and youtube_list_videos (listing). No ambiguity exists about what the tool returns.

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 the tool is for discovering trending content but does not explicitly state when to use it versus alternatives like youtube_search or youtube_list_videos. It provides parameter guidance (e.g., region_code) but no explicit 'use this instead of X' guidance, leaving the agent to infer context from the tool name and siblings.

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