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

Annotations already cover the read-only, idempotent, and non-destructive nature. The description adds meaningful context beyond annotations by stating that no key is required and that the result scope is the same as the public screen, plus the non-advice disclaimer.

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 brief and front-loaded with the core purpose, followed by scope and access notes. It is slightly redundant because the English parenthetical partially repeats the Korean content and the investment-advice disclaimer is not directly useful for invocation, but overall it stays compact.

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 no-argument, read-only listing tool, this description is complete enough: it states what is returned, the public scope, and the lack of a required key. No output schema exists, but the output is self-evident from the described ranking categories.

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 tool has zero parameters and the schema coverage is 100%, so the description does not need to explain parameters. The baseline for a no-parameter tool is 4, and the description does not introduce any misleading parameter-related information.

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 clearly states the specific resource and action: viewing top stocks by gain, loss, trading value, and relative volume. This semantically distinguishes it from sibling tools like market_indicators and market_map, even though no sibling is named.

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 useful context by saying the tool matches the public screen scope and requires no key, but it does not explicitly say when to prefer this over alternatives or when not to use it. Usage is implied rather than fully specified.

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