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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so the safety/mutation profile is covered. The description does add one genuinely non-structured behavioral rule (do not fabricate missing personal data), but says nothing about duplicate handling, required-field failures, or what a successful save returns.

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, front-loaded sentences with no filler; the action is stated first and the constraint second. It is efficient, though the terseness is partly under-specification rather than disciplined concision.

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 10-parameter, 6-required mutation tool with zero schema descriptions and no output schema, this description is far too thin. An agent gets no field guidance, no create-vs-update disambiguation, and no expectation of the write's result.

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% across 10 parameters with 6 required, so the description must carry the semantic load and does not. It only indirectly implies that required fields (recipientName, phoneNumber, formattedAddress, etc.) must be supplied by the user rather than guessed, with no field-level meaning added.

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 a specific verb and resource ('Save a delivery address'), which distinguishes it from the read/delete siblings customer_address_list, customer_address_delete and customer_address_update. It does not, however, state the boundary against customer_address_update, which is the closest sibling.

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 statement of when to create versus update an existing address, no mention of prerequisites, and no named alternative. The single constraint ('Never infer missing personal information') is a data-handling caution, not usage routing.

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