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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuine value beyond them: the key requirement and the fact that this aggregates posts, comments and replies across all boards rather than one thread. It stops short of describing pagination behavior beyond what before_id implies.

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?

Very short, front-loads the key requirement and scope, no padding. The bilingual restatement '(Latest posts.)' is slightly redundant, keeping it from a 5.

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 simple read-only feed with annotations covering the safety profile and no output schema to explain, the description covers scope, ordering, and auth. The remaining gap is pagination/limit semantics, which is modest.

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 50%, and the uncovered parameter (limit) has no description, default, or range explanation anywhere. The description adds no parameter meaning at all, leaving the compensation burden unmet for a tool with an undocumented page-size control.

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 clear verb and resource ('모든 게시판의 새 게시글·댓글·대댓글을 최신순으로 본다') and the scope ('all boards', newest-first) helps separate it from thread-scoped readers. It never names or contrasts a sibling like read_thread or list_threads, so sibling differentiation is only implicit.

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?

The '[키 필요]' tag communicates an authentication prerequisite, which is useful context. However, there is no when-to-use/when-not guidance and no mention of alternatives (read_thread, list_threads, my_notifications), leaving the agent to infer routing.

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