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

With no annotations, the description carries the full burden and does well: it discloses the 14-day input cap, that shifts past midnight are handled, how breaks are treated, and the exact overtime rule sets (federal 40h/1.5x vs. state daily rules). It does not state whether this is a pure computation with no side effects, nor any rounding/precision behavior for currency.

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, each densely packed with operative facts (limits, formats, break handling, overtime variants, optional pay output), with the core computation front-loaded. No filler or restatement of the title.

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 4-parameter calculator with no output schema, the description covers inputs, constraints and the two categories of result (overtime split and gross pay). What it omits is the shape of the response — e.g. per-day vs. per-week totals and how the overtime figures are returned — which an agent would need to use the result.

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, and the description earns an extra point by explaining the 7-days-per-workweek ordering constraint and that the weekly threshold defaults to 40 when no state is supplied. The state enum's daily-rule semantics are also restated in prose rather than only in the field description.

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 uses a specific verb ('adds up a time card') with explicit scope limits (up to 14 days, 7 per workweek), break subtraction and midnight handling, plus overtime and gross-pay computation. It is clearly distinct from convert_decimal_hours and split_tip_pool, but it never addresses the overtime_pay sibling, which overlaps on the overtime calculation, so differentiation is incomplete.

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?

Usage conditions are concrete: state rules apply only for CA/AK/NV/CO, the weekly threshold applies when no state is given, and gross pay is only produced when an hourly rate is supplied. There is no explicit exclusion or routing statement versus overtime_pay, which keeps it out of 5 territory.

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