get_derivatives_bars_daily_options_225

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=true, covering safety and idempotency. The description adds plan accessibility and scope (Nikkei 225 options) but does not provide additional behavioral details such as rate limits or data completeness. The mention of 'OHLC bars' is present but does not significantly extend beyond annotations.

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 concise and well-structured: it opens with the core purpose, then provides usage guidance, and finally documents the parameter. No extraneous information is present.

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 simple tool with one parameter and an output schema, the description covers the essential aspects: purpose, usage context, alternative tool, plan availability, and parameter format. It is complete.

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 input schema has 0% description coverage, so the description must compensate. The description specifies the parameter 'date' with format 'YYYYMMDD or YYYY-MM-DD' and marks it as required, which adds value beyond the schema that only declares its type as string and required.

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 tool returns 'Daily Nikkei 225 options OHLC bars', specifying the underlying asset (Nikkei 225) and data type (OHLC bars). It explicitly distinguishes itself from the sibling 'get_derivatives_bars_daily_options' by noting that the sibling provides full options data including TOPIX options and IV.

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 explicit guidance on when to use this tool (for Nikkei 225 options, simplified daily bars, accessible on Standard plan) and when to use the sibling (for full options including TOPIX and IV, Premium only). It also states the supported plans (Standard/Premium).

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