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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful behavior beyond that: replies are identified via parentId, pagination is cursor-based only on TikTok/YouTube, and YouTube review-held comments surface with isHidden true.

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?

Four tight sentences, each carrying a distinct fact (scope, default post, reply linkage, pagination, hidden comments), with the core purpose front-loaded and no filler.

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 no output schema, the description does useful work describing return semantics (parentId, isHidden) and pagination, and it covers the two required params. It is only slightly incomplete in not addressing profileId or default ordering beyond 'newest post'.

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 only 40%, so the description must compensate, and it does for postId (omittable to get the newest post) and cursor (fed from nextCursor). However it says nothing about profileId, and platform/accountId meaning rests on the schema itself, leaving part of the gap unfilled.

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?

States a specific verb (List) and resource (comments) scoped to one post across four named platforms, which cleanly separates it from siblings like list_posts and list_messages. An agent can identify the tool without opening the schema.

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?

Gives real usage rules: omit postId to target the newest post, and pass nextCursor back as cursor for the next page on TikTok/YouTube. It does not name when to prefer a sibling (e.g., reply_to_comment or delete_comment for other comment operations), so it falls short of explicit alternatives.

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