detect_ytd_high_low

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

Annotations already provide readOnlyHint, idempotentHint, destructiveHint. Description adds value by explaining comparison against first trading day of calendar year, alignment with Kabutan/Yahoo convention, default cache hit, and data availability time (17:15 JST). No contradiction.

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 clear sections (purpose, usage, behavior, args). It is reasonably concise but includes some redundant lists (supported plans repeated). Still effective.

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, the description does not need to explain return values. It covers purpose, usage, parameter semantics, behavioral caveats (date range, data availability), and caching. Comprehensive for a screening 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?

Despite 0% schema description coverage, the description includes an 'Args' section that explains each parameter in detail (date range, code optionality, min_prior_sessions meaning, detail flag). This adds significant meaning beyond the bare schema.

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 screens for year-to-date high/low records, using specific verbs ('Screen for', 'detect') and resource ('YTD high/low'). It distinguishes from sibling tools detect_ytd_high_low_range and detect_52w_high_low.

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?

Explicitly specifies when to use (年初来高値, 年初来安値, YTD high/low) and when not to (multi-date use range, 52-week use other tool). Also mentions supported plans and cache behavior.

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