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

No annotations are present, so the description carries the behavioral disclosure burden. It usefully discloses the calculation scope (federal, FICA, state) and that it uses the latest limits, but it leaves ambiguity about 'CDN limits' and does not explain how optional inputs like state or marginalRate affect the calculation or what the output looks like.

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 compact and front-loaded, with the core action in the first sentence. The phrase 'Latest CDN limits' is unclear and slightly undermines the otherwise efficient structure.

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 five-parameter calculator with no output schema and no annotations, the description gives the calculation scope but leaves meaningful gaps: whether state tax is included when state is omitted, what 'CDN limits' refers to, and what the returned value represents.

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 schema already documents all five parameters. The description adds no parameter-level detail beyond broadly mentioning contributions and state, which matches the baseline for fully covered schemas.

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 ('Calculate') and a specific resource ('tax savings from HSA and FSA contributions'), then sharpens scope with 'Federal + FICA + state tax savings.' This clearly separates it from sibling tax calculators such as calculate_payroll_tax or calculate_freelancer_tax.

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 intended use case is implied by the description: it is for HSA/FSA contribution tax savings. However, it never explicitly states when to choose this tool over the many sibling tax calculators, nor does it mention exclusions or alternatives.

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