youtube_videos

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

With no annotations, the description carries the full burden and does well: it discloses the required YOUTUBE_API_KEY, quota consumption of about 101 units per call, and the fallback behavior of returning setup instructions if no key is saved. It does not cover API error cases, but the main behavioral traits are 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 well organized into purpose, preconditions, arguments, and return value, with the main purpose front-loaded. There is slight redundancy in repeating view/comment counts in both the opening and the Returns section, but overall it is compact 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?

For a 3-parameter tool with an output schema, the description is complete: it covers setup, quota, parameter semantics, return shape, and the no-key fallback. An agent has enough context to select and invoke the tool correctly without needing additional documentation.

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 Args section is essential and fully compensates. It defines query as search terms, explains limit is capped at 25, and clarifies published_after_days filters to the last N days or can be omitted for any time period. This adds real meaning beyond the bare schema types and defaults.

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 opens with a specific verb and resource: 'YouTube videos matching a query, with view and comment counts.' It also clarifies the tool's role as a consumer-interest signal compared to search volume, making it distinct from unrelated siblings like reddit_signal, news_coverage, and related_topics.

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 provides clear use context: to measure how much people watch content about a topic, with examples like tutorials and reviews, and notes this is often stronger than search volume. It includes the important API-key prerequisite, but does not explicitly say when to prefer an alternative sibling or when not to use this tool.

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