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

Annotations already flag a non-readOnly, non-idempotent, non-destructive open-world write. The description adds genuine value beyond them: no shipment is created and no cost is incurred, the return is an id, and the record cannot be deleted through this server — a meaningful irreversibility warning that annotations alone do not convey.

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?

Three short sentences, front-loaded with the WRITE marker, then scope, then return value and endpoint. Every sentence carries information an agent needs.

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 single-object write with no output schema, the definition covers the operation's side effects, what is returned (an id), and the endpoint. The only meaningful omission is guidance on the address object's contents, but the nested schema documents most fields.

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 reported as 0%, and the description says nothing about the single nested 'address' object — not which fields are required (street, zip_code, city, country) nor the ISO-2 country format or the 'give last_name or company' rule. The nested property descriptions carry that knowledge, so the description fails to compensate for the coverage gap.

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 verb and resource ('save an address in the shipcloud address book') and immediately scopes it away from shipment creation with '(no shipment, no cost)'. An agent can distinguish it from shipcloud_create_shipment_with_label and shipcloud_get_address without opening the schema.

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 '(no shipment, no cost)' qualifier gives clear context on when this is the right tool versus label-creating siblings, and the note that the address cannot be removed through this server informs the use decision. It stops short of explicitly naming the alternative tools or stating prerequisites, so it is clear context rather than full routing.

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