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 fully covered. The description adds useful behavioral caveats: that median can be affected by housing-type mix, that years with 1-2 announcements shouldn't be read as a trend, and that the metric uses supply-area pyeong maximum price excluding balcony/options. However, it still doesn't disclose return format or pagination, and the caveats, while helpful, are somewhat scattered.

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 dense and somewhat repetitive: the first two sentences say almost the same thing ('같은 지역 분양 공고들의 연도별 평당 분양가 추이를 낸다' twice). It front-loads the core purpose but then mixes usage rationale, metric definition, caveat, and sibling positioning without clear structure. It could be trimmed.

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 and full annotation coverage, the description needs to convey what the tool produces and when to use it. It covers the metric definition, caveats about data quality, and how it relates to sibling tools. The main gap is the lack of explicit usage conditions (when to choose this over alternatives), but overall it's fairly complete for a trend-extraction 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 coverage is 100%, so the schema already documents all five parameters. The description only adds a note that exclusive_m2_min/max should be used to fix unit size (e.g., 80-85 for national pyeong) and a warning that sigungu is corrupted for Sejong, which is valuable beyond the schema. But it doesn't explain the region or keyword parameters beyond what the schema already provides, so it's a marginal addition.

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 ('연도별 평당 분양가 추이' for same-region presale notices) and contrasts itself with siblings realty_presale_vs_market and realty_region_price_stats. It clearly carves out its niche as '시분가끼리의 시계열'. The '축' framing is slightly abstract but the core purpose is unambiguous.

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 description indicates this axis answers the 'wait or not' question, especially under a re-application restriction. But it doesn't state explicit when-to-use or when-not-to-use conditions beyond mentioning siblings. It names the alternatives but doesn't provide clear selection criteria (e.g., 'use this when you want cross-announcement trends, not single-announcement fairness').

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