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

With no annotations, the description carries the full burden of behavioral disclosure. It explicitly states the tool is a 'heuristic proxy' and 'not a simulation' of YouTube's review process, which sets accurate expectations about its accuracy and scope. It also discloses that only the summary risk band, numeric score, and most severe flag are returned, while full details are excluded. This is meaningful behavioral context beyond what the schema provides.

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 compact at three sentences and front-loads the core action and criteria before caveats. Every sentence contributes: the first defines the scope and checks, the second specifies outputs, and the third clarifies the tool's heuristic nature and points to a paid alternative. There is no redundant wording or unnecessary detail.

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 a simple one-parameter schema and no output schema, the description provides sufficient context: what is checked, what is returned, and how the tool relates to YouTube's official process. It could mention edge cases (e.g., invalid channel) or error behavior, but these are not critical for a heuristic check tool. The description is complete enough for an agent to decide whether and how to invoke it.

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 schema already provides 100% coverage for the single parameter 'channel', including accepted formats (handle, URL, or channel ID). The description does not add any parameter-level detail beyond implying the channel is used to analyze recent uploads. Since schema coverage is high, the baseline of 3 is appropriate; the description does not need to repeat schema information.

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 uses a specific verb ('Check') and clearly identifies the resource ('a YouTube channel's recent uploads') and the specific policy criteria (title/description repetition, upload-cadence regularity, AI-disclosure language). It also states the exact return values (risk band, numeric score, most severe flag) and explicitly distinguishes itself as a heuristic proxy, not a simulation. This leaves no ambiguity about what the tool does.

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 clearly implies the primary use case: assessing a channel's AI-slop risk. It also provides an implicit exclusion by noting that the full flag-by-flag report with exact numbers and fixes is a separate paid product, telling the agent when NOT to use this tool (if detailed reporting is needed). No sibling tools exist, so explicit alternative routing isn't required.

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