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

Annotations already signal non-read-only, non-destructive, and idempotent behavior. The description adds useful context: reference images are not modified, the result is always a new image, and each image costs 25 points. It does not contradict any annotation.

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 short and front-loaded with the core function and key caveats. The only minor redundancy is the cost being stated twice: '장당 25포인트입니다' followed by '[이미지당 25포인트]'.

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 6-parameter tool with no output schema, the description covers generation modes, reference semantics, and cost, while the schema covers input details. The main gaps are the lack of explicit sibling differentiation from batch/editing tools and no indication of what the response contains.

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?

The schema covers all 6 parameters with 100% description coverage, so the baseline is 3. The description adds no parameter-level detail beyond the schema; the reference-image semantics ('제품·인물·색감·구도') are already present in the schema property description. Cost is additional context but not parameter semantics.

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 action and resource: '이미지 한 장을 생성합니다' — generate one image. It distinguishes itself from siblings by emphasizing '한 장' (single image, vs image_batch_create) and '결과는 새 이미지' (new image, vs edit-like operations).

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 gives clear context for the two input modes: text-only or reference image plus text, and explains the reference image is only a guide. However, it does not explicitly state when to choose this tool over image_batch_create or image_edit, nor does it list exclusions, so the routing decision is mostly implicit.

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