get_index

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds that it returns current index values, which is useful context, but doesn't disclose details like whether it returns both indices together or separately, or the exact response format. With annotations covering the safety profile, a 3 is appropriate.

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 compact and front-loaded, with the core purpose stated first and example queries following. It's slightly redundant with the title and could be more concise, but every sentence earns its place by clarifying usage context.

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 zero-parameter read-only tool with an output schema present, the description is largely complete. It tells the agent what the tool does and when to use it. The only minor gap is not specifying whether the response includes both indices in a single call or if separate calls are needed, but the output schema likely covers this.

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, so the schema provides no parameter documentation. The description compensates by explaining what the tool returns (KOSPI and KOSDAQ current values) and giving example queries. With 0 params, baseline 4 is correct, and the description adds meaningful context about the tool's scope.

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: 'get_index' retrieves current index values for KOSPI and KOSDAQ. It clearly identifies the tool's purpose and distinguishes it from sibling tools like get_price or get_market_clock, though it doesn't explicitly name a sibling alternative.

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 provides clear context for when to use this tool, listing example queries like '코스피', '코스닥', '시장 지수', and '오늘 시장 어때'. It implies this is the go-to tool for Korean market index queries, though it doesn't explicitly state when not to use it or name alternatives.

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