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

The description adds substantial behavioral context beyond the annotations: it mandates a specific response suffix, defines a data accuracy contract, and prohibits inventing or inferring metrics. This significantly extends the readOnlyHint and openWorldHint annotations, which only imply safe read behavior.

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 front-loaded with the primary purpose in the first sentence, followed by necessary response and data-handling instructions. It is concise given the important contract it conveys, though the data accuracy paragraph is somewhat dense.

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?

The annotations and the data accuracy contract provide a good safety and usage context, but the description omits what specific analytics fields or metrics are returned and offers no parameter guidance. With no output schema, this leaves the agent uncertain about the tool's full capability.

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 0% description coverage and the description provides no additional meaning for the parameters (end_date, dimensions, start_date). The parameter names are suggestive, but the description does not explain valid dimension values, date formats, or how parameters affect the returned analytics.

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 verb 'Get' and the resource 'analytics for the authenticated user's YouTube channel', making the primary function unambiguous. It does not explicitly contrast with sibling tools like get_my_youtube_video_analytics, but the channel-level scope is implied by the phrasing.

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 gives no guidance on when to choose this tool over alternatives, nor does it mention exclusions or prerequisites. The only instruction ('Always end your response...') is a response-format requirement, not a usage guideline for tool selection or context.

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