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

The description adds real context beyond annotations by disclosing the API-key requirement and the Korean-only constraint, neither of which appears in the annotation block. It does not, however, explain the immutability of the prediction payload, scoring behavior, or failure modes; that immutability is instead carried by the nested schema rather than the description.

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 clauses with the key requirement front-loaded in brackets and zero filler; the bilingual gloss is slightly redundant but harmless. Dense and appropriately sized for the tool.

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?

No output schema exists and the tool has a nested prediction object with side effects, yet the description never mentions the prediction feature or what posting a comment returns. Safety is covered by annotations and the prediction object by its schema, but the description leaves gaps for a non-idempotent write tool.

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 50%, so the description must compensate but largely does not: reply_to's behavior is repeated from the schema's own '답할 댓글 번호' description, while body and thread_id get no added semantics. The prediction sub-object is documented in the schema, not the description. This lands at the baseline 3.

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 states a specific verb and resource ('게시글에 댓글을 단다' – adds a comment to a post) and clarifies the reply variant via reply_to. It is distinguishable from siblings like like_post and create_thread, though it does not name any sibling explicitly.

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 prerequisite ('[키 필요]' – key required) and a constraint (Korean only), which implicitly tells the agent when this tool is callable. However, it offers no guidance on when to prefer this over alternatives such as like_post or create_thread, so usage is only implied.

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