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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false. The description adds valuable behavioral context by noting that explicit confirmation and an idempotency key are required, which goes beyond the annotations. It does not detail rate limits or auth, but the added requirements are meaningful.

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?

Two short sentences are front-loaded with purpose and key requirements. Every sentence earns its place with no filler.

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?

Given four required parameters, no output schema, and existing safety annotations, the description covers the critical behavioral requirements (confirmation and idempotency). The remaining parameters are intuitive from the tool name, so the description is nearly complete, though a bit more on contactId/text semantics would help.

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 0%, so the description must compensate. It partially does by linking 'conferma esplicita' to the confirm param and 'idempotency key' to the idempotencyKey param, but it does not explain contactId or text beyond implication. Coverage is incomplete but not absent.

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+resource: 'Aggiunge una nota a un contatto' (adds a note to a contact). It clearly distinguishes the action from sibling read/search tools like contacts.get or contacts.search.

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?

It states prerequisites ('Richiede conferma esplicita e una idempotency key'), which implies when the tool can be used, but it does not mention alternatives or when-not-to-use conditions. Usage is implied rather than fully guided.

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