youtube_channel_overview

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds nothing beyond the annotations: no note about public-data-only access, rate limits, or what happens with an invalid channel, and since an output schema exists the return shape need not be restated.

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?

One short sentence with zero filler and the key metric scope front-loaded. It is efficient, though the terseness borders on under-specification for a tool with no usage guidance.

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?

With an output schema covering return values and annotations covering safety, the main missing piece is usage guidance and any auth/quota caveats. For a simple single-parameter read tool this is minimally adequate but not complete.

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% and the single 'channel' parameter is documented in the schema with both forms ('UC...' or '@handle'). The description adds no parameter detail, so baseline 3 is appropriate.

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 phrase 'Subscriber, view and upload totals for a YouTube channel' names the resource and the exact metrics returned, so an agent knows this is a stats-summary tool rather than a listing tool. It lacks an explicit verb and does not name which sibling (e.g. youtube_recent_uploads) it differs from, but the metric scope is distinctive enough to separate it from the other youtube_* tools.

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?

There is no when-to-use guidance, no prerequisites (e.g. requiring a valid channel ID/handle), and no mention of alternatives among the youtube_* or instagram_* siblings. The agent must infer usage entirely from the metric list.

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