get_video_stats

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful scope (lifetime statistics) and plan availability, but it does not describe return shape, limits, or error behavior; that gap is acceptable given the annotations but not additive enough for a higher score.

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?

Two tight sentences with no filler. The result set is front-loaded, then the plan constraint, then the sibling routing; every clause adds 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 one-parameter, read-only stats tool with rich annotations and no output schema, the description covers what is returned, plan eligibility, and the relevant alternative. Nothing an agent needs to call it correctly is missing.

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%: video_id is already described as 'Video id.' The description adds no additional format, example, or source guidance for the parameter, so the baseline of 3 applies.

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: 'Get a video's lifetime play count plus its comment and like totals.' It explicitly names what data is returned and differentiates from get_video_analytics by naming the time-series/geography features that belong to the sibling.

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 gives a direct routing rule: use get_video_analytics for views over time, finish rate, and geography. It also notes this tool works on every plan while the alternative needs a paid plan, so an agent can select correctly without opening the sibling's schema.

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