Create ship-from address

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

Adds genuinely useful behavior beyond the annotations: US-only scope, that Pirate Ship normalizes and completes ZIP+4, that the new address is not made default, and that omitting return_address routes returns to the origin. It does not warn about duplicate creation, given idempotentHint=false, nor about the failure mode for invalid or non-US addresses, which leaves a gap for a mutation tool.

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?

Four short sentences, front-loaded with the action and followed by the two decision-relevant behaviors (return address fallback, ZIP+4 normalization) and the routing hint. Minor waste in the near-duplicate opening pair "Adds a US Ship From Address" and "Saves a new Ship From Address in Pirate Ship."

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, an agent still learns the essential semantics of a create call: what entity is persisted, how the return address falls back, ZIP+4 normalization, and that defaults are untouched. Still missing is what the call returns (e.g., an identifier for later update/delete calls) and error behavior for non-US or invalid addresses.

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 67%, and the description's return_address default restates what the schema already documents ("Where returns go. Default: the origin."). Several nested origin fields (zip, city, phone, company, full_name) carry no description in either place, and the description adds no format or validation guidance beyond the schema's maxLength/minLength constraints, so it only marginally compensates.

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 ("Adds a US Ship From Address") plus scope (US-only, optional distinct return address), which clearly separates it from update_ship_from_address, list_ship_from_addresses, and set_default_ship_from_address among the siblings. An agent can identify the operation 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?

Explicitly routes the agent away from this tool for the default-address case: "It does not become the default: call set_default_ship_from_address for that." It also implies when to supply return_address. It stops short of naming exclusions against update_ship_from_address (editing an existing address) or what to do when the address already exists.

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