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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description still adds real context beyond that: the output is an estimate that may be a single amount or a range, the result is jurisdiction- and statute-bound, and it explicitly disclaims legal advice. It does not mention rounding, assumptions, or failure modes, keeping it short of a 5.

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?

A single dense sentence that front-loads jurisdiction, scope, legal basis, input formula, and output shape with zero filler. Every clause earns its place.

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 not be explained, and annotations cover the safety profile. But for a 6-parameter financial calculator with 0% schema coverage, the description leaves key inputs (work_pattern, unpaid_days, total_monthly_wage_aed) undefined, which is a meaningful gap for correct invocation.

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 0% across 6 parameters, so the description carries the full burden and largely fails. It gestures at 'basic wage + dates' (mapping loosely to basic_monthly_aed, start_date, end_date) but says nothing about total_monthly_wage_aed, work_pattern, or unpaid_days — all of which materially change a gratuity calculation under the cited law.

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 precise verb and resource ('UAE private-sector end-of-service gratuity estimate') plus the governing statute (Decree-Law 33/2021 art. 51), so the agent knows exactly what computation is being performed. It does not, however, distinguish itself from the sibling 'labour_calculator', which an agent could plausibly confuse it with.

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 'basic wage + dates → amount or range' formula implies the required inputs and therefore when the tool is applicable, and 'not legal advice' sets a scope boundary. There is no explicit when-to-use vs. when-not-to-use guidance and no named alternative, so usage must be inferred.

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