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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds useful behavioral context beyond that: it discloses that pagination is supported via page and that each call costs 40 points ([호출당 40포인트]), which is a meaningful operational constraint not present in structured fields.

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 core information is front-loaded in the first sentence, which is good. However, the Korean sentences mostly restate the English content (returned fields, pagination), creating duplication that wastes space without adding new meaning.

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?

There is no output schema, so the description must describe return values; it does so by naming image URL, source page link, and title. It also covers pagination and cost. For a simple two-parameter read-only search tool, this is largely complete, with only edge-case behavior (e.g., invalid page handling) left unspecified.

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 100%, so the schema already documents both keyword and page (including the 1–5 range and 20 results per page). The description's mention of pagination reinforces the page parameter's purpose but adds no syntax or format detail beyond the schema, so baseline 3 applies.

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 specific verb and resource ('Google image search by keyword') and lists the returned fields (image URL, source link, title). It does not explicitly differentiate itself from other Google search siblings like google_search or google_lens_search, so it falls short of a 5, but the 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?

No guidance on when to use this tool versus alternatives such as google_search, google_lens_search, or google_shopping_search. The pagination note describes how to use the page parameter, not when to choose this tool over siblings.

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