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

Annotations already establish the safe read-only profile, and the description adds real operational context on top: the listing is not authoritative for eligibility (FTTH at the address is required), the voucher is issued by Open Fiber under its own conditions, and inactive initiatives must not be proposed. It stops short of describing the response shape or the meaning of fields other than inElenco/attiva.

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?

Roughly five sentences, each carrying distinct information (purpose, trigger, parameter effects, eligibility caveat, inactivity guard). Slightly dense in the opening clause, but front-loaded with the tool's identity before the usage rules.

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?

There is no output schema, so the description has to carry the return semantics, and it does explain the grouping and key fields (inElenco, attiva). It remains incomplete on the full response structure, but an agent can call it correctly and interpret the answer.

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, but the description goes beyond the schema by explaining the effect of each parameter on the result set: `comune` yields an inElenco membership answer, `provincia`/`regione` narrow the list, and no parameters returns everything.

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?

Names the specific artifact (the 100 € Open Fiber 'La Fibra che ti premia' voucher, activations by 31/12/2026), what it returns (conditions, dates, municipalities grouped by region and province), and clearly separates it from verifica_copertura, which is named as the different tool for address-level eligibility.

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?

Explicit trigger ('Usalo quando il cliente chiede del buono o di promozioni in un comune'), explicit filtering behaviour per parameter, an explicit handoff rule to verifica_copertura for the real check, and an explicit exclusion ('Con `attiva` false ... non proporla'). Nothing about when to pick this vs a sibling is left to inference.

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