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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so safety is covered. The description adds meaningful context beyond them: prices are live from the site ('non memorizzati') and the Open Fiber voucher note is time-limited ('finché dura'), which are genuine behavioral traits an agent could not derive from the 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 main purpose is front-loaded, but the body is a single sprawling sentence with a long comma/colon-separated enumeration and a semicolon clause. It is information-dense yet hard to scan; a short structured list of returned fields would serve the agent better.

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 carries the full return-value burden and largely meets it by enumerating the concrete fields (canone, sconti, router, costi di uscita, fatturazione, notaBuonoOpenFiber). Combined with the rich annotations, an agent has enough to call it correctly, though the enumeration is not exhaustively organized.

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% and the single enum parameter 'pubblico' is fully documented in the schema, so the schema does the heavy lifting. The description gestures at the concept ('per chi è l'offerta') but adds no syntax or filtering semantics beyond what the schema already provides; baseline 3 applies.

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 resource (the Interfibra price list) and enumerates exactly which attributes it returns (canone, router, costi di uscita, tempi di attivazione, etc.), so an agent understands the payload well. It does not, however, distinguish itself from the sibling dettaglio_offerta, which appears to cover a single offer rather than the list.

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?

There is no explicit when-to-use, when-not, or alternative routing. The phrase 'attivabile oggi' implies it surfaces currently activatable offers, but nothing tells the agent to pick this over dettaglio_offerta or verifica_copertura; the choice 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.