get_derivatives_bars_daily_options

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

Annotations already declare readOnlyHint and idempotentHint, so no contradiction. The description adds that it returns OHLC, volume, open interest, and implied volatility, and mentions the Premium plan restriction, which provides extra context beyond annotations. However, it does not disclose any edge cases or rate limits.

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 well-structured with a clear purpose upfront, followed by usage notes and parameter list. It is slightly verbose with Japanese terms and examples but still efficient and front-loaded.

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?

Given the output schema exists, the description covers return fields and parameter details adequately. It also provides context for when to use a sibling tool, making it complete for a data retrieval tool.

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 description provides comprehensive parameter details with format examples (e.g., date: YYYYMMDD or YYYY-MM-DD, category examples, contract_flag meanings). This fully compensates for the 0% schema description coverage, adding significant meaning.

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 it returns daily options OHLC bars with IV, specifying the resource (options) and verb (get). It explicitly distinguishes from the sibling tool for Nikkei 225 options, making its purpose unique.

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 explicitly notes when to use an alternative tool ('For Nikkei 225 options only (Standard+), use get_derivatives_bars_daily_options_225.'). It also indicates it is Premium only, giving clear guidance on plan restrictions.

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