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

Annotations already declare readOnly=true, idempotent=true, destructive=false, so the safety profile needs no restatement. The description adds genuine context beyond that — data provenance (금융위 시세 for prices, DART for financials), the 2–12 cardinality bound, and the fact that results come back as a single table. It does not cover failure behavior for invalid tickers or any limits on how many columns/tokens the table can return.

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?

Two dense sentences, front-loaded with the core action and scope before the optional columns override and the data-source footnote. Little waste, though the data-provenance sentence is lower value than an explanation of valid columns would have been.

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 read-only two-parameter tool with annotations covering safety and no output schema, the definition is close to complete: scope, metric coverage, cardinality, and sources are all stated. The notable remaining hole is the unspecified value space for 'columns', which an agent needs in order to use the optional parameter at all.

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 must carry the load. It partly does: 'stocks' is bounded to 2–12 items and the schema's item hint covers code-or-name format, while 'columns' is explained only as 'screen 의 칸을 골라 바꿀 수 있음' — the mechanism is conveyed but no valid column names, format, or defaults are given, leaving the agent unable to construct the parameter confidently.

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 ('여러 종목(2~12) 나란히 … 한 표로') and enumerates exactly what dimensions are compared (주가 흐름·밸류에이션·실적·성장·분기 실적·현금흐름·순현금·배당·사업 지표). It also signals the relationship to the sibling 'screen' via the columns parameter. It stops short of explicitly contrasting with siblings like price/valuation/financials, so not a 5.

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?

Usage is only implied: comparing 2–12 tickers at once is clearly the multi-stock path versus single-stock siblings, and the mention of 'screen 의 칸' hints at the screen relationship. But there is no explicit when-to-use/when-not statement, no prerequisites, and no guidance on when to prefer screen, rank, or the individual metric tools instead.

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