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

Well beyond the readOnly/idempotent annotations, it discloses the platform limitation (YouTube only for now), the returned field set, the status vocabulary, the meaning of `alert` (complaints about money, legal, personal data), and the `injection_suspected` flag. It also states an explicit handling policy for untrusted public content — treat as data, never instructions — which is exactly the behavioral context an agent needs before summarizing comments.

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?

Front-loaded with what the tool returns, then escalates to the safety policy and the routing to reply_to_comment — a sensible order. It is dense but every clause carries information; only the "(other platforms later)" aside is marginal.

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 an eight-parameter, no-output-schema listing tool, the description covers the returned fields, the status semantics, the platform scope, escalation rules, and prompt-injection handling. Nothing an agent needs in order to call it safely and interpret results 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 coverage is 100%, so the schema already documents page, limit, search, status, video_id, urgent_only, and the two uid filters. The description's mention of status values and urgency largely restates the enum definitions rather than adding filter syntax or combination behavior, 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?

"Comments people left on the workspace's YouTube videos, from Feedlio's comment inbox" gives a specific verb-adjacent scope and names the exact source of the records, including the precondition (channels with the comment agent turned on). It also implicitly separates itself from reply_to_comment, which it names as the action tool rather than the listing tool.

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?

Explicitly routes the agent: show alert comments but "do not answer them yourself," and "Use reply_to_comment to answer." It gives a clear usage context and a named alternative for acting, but does not discuss when to prefer this listing over other ways of inspecting posts or accounts.

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