Validate Partita Iva Format

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

With no annotations provided, the description carries the full responsibility for behavioral disclosure, and it excels. It details the processing steps (strips whitespace, checks exactly 11 digits, applies the official algorithm) and explicitly states the return object for both success and failure, including the error key. This fully reveals behavior without contradicting any metadata.

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 efficiently structured: a first sentence stating the core purpose, a second providing usage context and alternatives, and a third with processing details, followed by a precise return-format specification. Every sentence contributes value, and the most important information is front-loaded.

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 simple single-parameter validation tool, the description is comprehensive. It covers why to use it (step 1 in workflow), how it behaves (stripping, check algorithm), and what it returns (valid/value/error). No information needed for an agent to call it correctly is missing, even given the output schema is present.

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%, and the schema's description of the partita_iva parameter already includes 'Italian Partita IVA (VAT number) to validate. Must be exactly 11 digits. Whitespace is stripped before validation.' The tool description does not add meaning beyond this for the parameter itself—it repeats the same facts. Thus, a baseline of 3 is appropriate per the calibration guidance.

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 states a specific verb ('validate'), a clear resource ('Italian Partita IVA'), and the exact criteria (11 digits and modulo-10 checksum). It explicitly distinguishes itself from the sibling validate_partita_iva by naming the alternative and the condition to choose it, leaving no ambiguity about what the tool does or how it differs.

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 provides explicit usage context: 'Use this as step 1 in the invoice generation workflow before any other tool.' It also gives a clear when-to-use vs. when-not-to-use by contrasting with validate_partita_iva: 'use this standalone version when you only need the validation result without importing header tools.' This is direct, actionable guidance.

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