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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description still adds real behavioral context: it is deterministic, derived from an official fee table with sources, flags unverified mission/courier figures, and is information-only.

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?

Front-loaded with the core purpose in the first clause, followed by the fee components and then two short qualifier sentences. Dense but each clause carries fee-structure information; the single long sentence is slightly heavy but not padded.

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?

An output schema exists so return values need no explanation, and annotations cover the safety profile. The description enumerates every fee component and its conditions, leaving only minor gaps such as how missing optional inputs (month, location) are handled by default.

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 the baseline is 3. The description goes beyond the schema by attaching concrete fee semantics to the parameters (seasonal €70/€80 adult rates, €160 urgent service with 4-hour window, €15 lost-but-valid supplement), which enriches parameter interpretation.

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: an itemised government fee estimate for a Maltese passport, with the authority (Identità) named. It is easy to distinguish from get_passport_renewal or estimate_total_cost by scope, but it never explicitly routes against those sibling estimators.

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 description explains what the estimate contains but gives no when-to-use guidance or alternatives. The only directive, 'confirm with the Passport Office or mission before paying,' is a reliability caveat rather than a rule for choosing this tool over estimate_total_cost or get_passport_renewal.

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