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

Annotations declare readOnlyHint=true and openWorldHint=true, and the description's '获取' aligns with this. The description adds useful behavioral context beyond annotations: it explicitly limits results to first-level comments and, through the page_token parameter description, discloses strict opaque pagination rules (no modification, no cross-content/sort/entry reuse).

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 a single front-loaded sentence with no filler. It efficiently conveys the core purpose and scope without repeating structured 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?

The schema descriptions, output schema, and readOnly annotation make the definition substantially complete for correct invocation. The only notable gap is the absence of an explicit statement about when to prefer this tool over the by_url or reply siblings, though the names and parameter guidance largely compensate.

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 schema itself provides rich, precise meanings for all three parameters, including detailed guidance for content_id formats and opaque token handling. The top-level description adds no additional parameter semantics beyond what the schema already supplies, 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 uses a specific verb ('获取') and resource ('一级评论列表') scoped to videos, articles, and dynamics keyed by Bilibili content ID. This clearly distinguishes it from sibling tools such as the by_url variant and the replies-by-comment_id 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?

Use is implied by the description and tool name: this is the ID-based entry point for first-level comments. However, the description never explicitly states 'use by_url when you have a URL' or contrasts with the reply tool, so the agent must infer tool selection from sibling names rather than receive direct routing guidance.

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