tax_us.fica

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

Annotations already declare the tool as read-only, deterministic, and closed-world. The description adds substantial domain-specific behavior: it explains how additional Medicare 0.9% is split between employer withholding and filing_status-based settlement, clarifies that social security base is per-employer, and states the output format (USD annual total strings) and rounding policy. This goes well beyond the safety profile in annotations.

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?

The description is dense but front-loaded, starting with the core purpose and then layering rounding rules, Medicare nuances, limitations, and a misuse example. Every sentence adds necessary information without redundancy, making it efficient for a complex calculation tool.

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?

Given the tool's complexity (10 parameters, no schema descriptions), the description provides strong context on tax logic, rounding, and limitations, and an output schema exists so return values need not be detailed. However, it omits explanations for several parameters (mode, as_of, include_proposed, other_medicare_wages), leaving some gaps for an agent to infer.

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?

With 0% schema description coverage, the description compensates for several parameters: year (tax-year policy), wages (annual total), net_profit (92.35% of net profit for SECA), decimals/rounding (rounding behavior and default HALF_UP), and filing_status (thresholds for additional Medicare). However, it leaves mode, as_of, include_proposed, and other_medicare_wages undocumented, so it only partially fills the gap.

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 specifies the exact taxes calculated (FICA under IRC 3101/3111 and SECA under IRC 1401) and distinguishes the tool from siblings like federal_income by focusing solely on payroll and self-employment taxes. It also clarifies the scope as a tax-year policy calculation, leaving no ambiguity about what the tool does.

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 explicitly lists what the tool does not cover (multiple employer over-withholding refunds, optional calculation methods, RRTA, spouse self-employment income aggregation) and provides a concrete misuse example ('putting a single pay period's salary as annual wages'). It does not name alternative tools to use instead, but the exclusions and misuse guidance give clear context for when to use or avoid this tool.

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