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

Annotations already declare readOnly, idempotent, non-destructive and closed-world behavior, so the safety profile is covered. The description adds real value beyond them: the pinned 2026 coverage window, the exact formula applied (weekly-rest baseline plus statutory events and PF-257 transfers), and a documented REST fallback with a warning not to guess other /api/* paths.

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?

It is front-loaded with the routing decision, then example requests, inputs, and callable JSON examples, which is a sensible order. However, the enumerated output fields are redundant with the existing output schema and the formula line is terse jargon that adds length without much clarity.

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 two-parameter, single-purpose calculation tool, everything needed to invoke it is present: inputs, argument examples, fallback endpoint, and docs link. The only gap is the unnecessary outputs enumeration, which duplicates the output schema rather than adding information.

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 100%, so both parameters (date, workweek) are already fully documented including the 5 = Saturday-Sunday / 6 = Sunday-only semantics and the 2026 pinning. The description repeats the input list and adds worked JSON examples, but contributes no meaning beyond the schema, so the 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?

The description names a specific verb and resource ("Checks a date against Uzbekistan's 2026 statutory holidays") and pins the scope (nationwide, 2026, five- or six-day workweek). An agent can distinguish it from add_uzbekistan_working_days and count_uzbekistan_working_days by the singular date-check semantics stated here.

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?

It gives an explicit when-to-use rule (auditable nationwide 2026 result with known workweek) and a when-not-to-use rule (workweek unknown, continuous/shift-based/employer/bank/school/sector rosters). It also instructs the agent to prefer this tool over answering from memory, but it never names the sibling add_/count_ tools as the alternative for adjacent tasks.

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