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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavioral context with platform availability and the nested-reply mode, but says nothing about pagination behavior despite limit/cursor parameters being present.

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?

Three short sentences, front-loaded with the core action and resource, then the reply mode, then the platform exclusions. No filler or redundant restatement of the title.

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 a 5-parameter tool with zero schema description coverage and no output schema, the definition leaves account_id, limit, and cursor entirely undocumented and references a nonexistent social_id field. The platform scoping and reply mode are good coverage, but an agent could not confidently paginate or supply the account parameter from this text.

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 0%, so the description carries the full burden, yet it only addresses comment_id meaningfully. Worse, it instructs the agent to 'pass its social_id', a parameter that does not exist in the schema (the actual field is post_id), which actively misleads. account_id, limit, and cursor receive no explanation at all.

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 names the specific resource (comments) and the two platforms it works on (LinkedIn, Instagram), and explains the reply-listing mode via comment_id. It does not name the closest sibling (list_user_comments) or distinguish itself from list_comment_reactions, so sibling differentiation is only partial.

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?

It gives a clear when-not signal by excluding Messenger, X, and WhatsApp, and states the condition that switches behavior (pass comment_id to list replies). It stops short of pointing to an alternative tool for the unsupported platforms or for user-scoped comment listing.

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