Is it a holiday / business day?

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

'Works offline' largely restates openWorldHint=false, and readOnlyHint/idempotentHint already cover safety. The valuable addition is the output taxonomy (weekend / full holiday / half day / business day), which goes beyond annotations, but no response shape or edge behavior (e.g., unknown dates, half-day semantics) is given.

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?

Two tight sentences, front-loaded with the core question and the domain constraint. Nearly zero waste; only 'Works offline' is marginal given the annotations.

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?

With one optional parameter, full schema coverage, and no output schema, the main missing piece is output shape — partially covered by listing the possible classifications. Adequate for an agent to invoke correctly.

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 coverage is 100% and already documents the YYYY-MM-DD pattern and the today-in-Türkiye-time default. The description adds no parameter detail beyond that, so baseline 3 applies.

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?

States a specific verb+resource: tells whether a date in Türkiye is a weekend, public/full or half holiday, or business day. The classification taxonomy makes it distinguishable from list-style siblings like get_public_holidays, though no sibling is named.

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 'is it a business day?' framing implies use (e.g., before scheduling), but there is no explicit when-to-use vs get_public_holidays, add_business_days, or count_business_days. An agent must infer the boundary itself.

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