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

Annotations already declare the safe/idempotent read profile, but the description adds real behavioral context beyond them: exact coverage boundaries, calendars explicitly NOT inferred, Qurban Ait handling, and the Constitution Day legal-transition caveat. It also supplies the iteration formula and a canonical REST fallback path.

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?

Section labels (What it computes, Inputs, Outputs, Formula, Docs) front-load usefully, but the Adilet/Constitution Day passage is dense legal detail of marginal value to a caller, and the 'Do not use this when this package covers...' clause is a malformed run-on. Several sentences do not earn their place for tool-selection purposes.

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 an output schema and annotations already present, the definition still covers enough for correct invocation: scope limits, formula, example arguments, and error-avoidance guidance. The Outputs field list redundantly duplicates the output schema, but nothing an agent needs to call it is missing.

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% and both parameters (start_date, working_days) are already fully documented in the schema, including the sign convention. The description restates the inputs and adds a JSON example, but contributes no meaning beyond what the structured schema already provides; 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 (add/subtract Kazakhstan working days) and its scope precisely: the nationwide published 2026 five-day schedule over a Saturday-Sunday baseline. It names the country-specific coverage that distinguishes it from the ~60 sibling country tools, so an agent can select it without opening schemas.

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?

Provides an explicit 'use this when' trigger (deterministic Kazakhstan working-day offset, prefer the calculator over memory or stopping at discovery) and a 'do not use' clause listing excluded calendar types (six-day, shift, continuous-operation, employer, bank, school, local, sector). The do-not-use sentence is grammatically garbled, and it does not name sibling alternatives like count_kz_working_days or check_kz_working_day, so it stops short of a 5.

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