detect_ytd_high_low_range

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

Annotations already indicate read-only and idempotent behavior. The description adds useful context: data availability at 17:15 JST on trading days, cache-only for plans, and that setting 'code' bypasses pre-computed cache. No contradictions.

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 mostly concise and front-loaded with key points. Minor redundancy: 'All plans.' at start is repeated in the supported plans line. Nonetheless, it is efficient.

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 presence of an output schema and comprehensive parameter explanations, the description provides sufficient context for an agent to use this tool correctly, including when to prefer over siblings.

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 0%, but the description provides clear explanations for all parameters: date_from within 52 weeks, date_to inclusive, code optional and its effect, min_prior_sessions referencing sibling, detail default false. This fully compensates the lack of schema descriptions.

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 scans year-to-date high/low records across a date range. It uses a specific verb and resource, and distinguishes itself from the sibling tool detect_ytd_high_low by emphasizing multi-day queries.

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?

Explicit guidance is provided: 'Use this instead of repeated detect_ytd_high_low calls for multi-day queries. Issue one range call — splitting into parallel range calls defeats the purpose.' Also includes plan support and data availability timing.

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