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

Beyond the readOnlyHint and openWorldHint=false annotations, the description discloses the default 45-day window, the differing result shape between queried and unqueried calls, and that the data is in Russian — a genuinely important operational fact an agent would otherwise miss. Gaps remain: it says nothing about the interplay between limit and the 45-day default window, or whether the window can be widened.

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 sentences, tightly packed, with the resource and domain enumeration front-loaded and the query/default behavior immediately after. The parenthetical list and the note about Russian add information rather than noise; nothing is wasted.

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 read-only, two-optional-parameter tool with no output schema, the description covers the essentials: what is returned (deadlines with legal sources), what the modes are, and the language of the data. The only shortfall is the lack of guidance on the limit default and any pagination/truncation behavior, which is minor at this complexity.

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%, so the baseline is 3, but the description goes further by explaining that the query is a topic-matching mechanism over rules and that matches are returned with their next date — output-shape semantics the schema does not convey. The limit parameter's role is left entirely to the schema, which is the only reason this is not a 5.

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 concrete resource — a calendar of statutory deadlines for businesses in Uzbekistan — and enumerates the covered domains (tax returns and payments, financial statements, statistics, corporate and HR), plus the legal source attached to each entry. That is far more specific than the sibling tools (article search, company info, fees) and makes the tool unmistakable.

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 clearly explains the two operating modes: no query returns deadlines in the next 45 days, while a query returns matching rules with their next date. That is effectively a when-to-use rule for the query parameter. It stops short of naming alternatives or stating what kind of question this tool should not answer, so it is clear context without explicit exclusions.

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