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

Annotations already declare this a pure read-only, idempotent, closed-world computation, so the bar is lower; the description earns credit by disclosing the exact computation method (IRS worksheet), the phase-out formula, and source provenance for the amounts. It stops short of describing the response shape or units of the returned comparison.

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?

Purpose is front-loaded in the first clause and every sentence carries substantive information, but the middle sentence is a dense run-on of statutory dollar amounts that is harder to scan than a short list. No filler, though.

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?

With no output schema, the description should say what comes back; it implies a deduction amount plus an optional itemize-vs-standard comparison but never names the returned fields. Parameters and computation logic are otherwise fully covered for a calculator of this complexity.

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 baseline is 3. The description adds formula-level meaning for how magi and tax_year drive the cap and phase-out, but it does not add per-parameter guidance beyond what the schema descriptions already state (e.g., filing_status enum handling, behavior when state_and_local_taxes is below the cap).

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 (calculates) and resource (SALT deduction on Schedule A), plus the governing statute and year range. It is unambiguous against siblings like calculate_car_loan_interest_deduction or get_tax_brackets_and_standard_deduction, since the tax item is named explicitly.

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 implies usage ('Optionally compares itemizing with the standard deduction') and explains that other_itemized_deductions is only needed for that comparison, but it never says when to call this versus the sibling standard-deduction tool or what to do for years before 2025/tax years outside the modeled window. Usage is inferable, not stated.

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