Get shipping rates

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-dependency context are covered. The description adds that rates may differ from estimate_order_costs when store shipping settings apply, which is useful behavioral context. It does not describe return shape, rate variability details, or error behavior, so it adds only moderate value beyond 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?

Three short sentences, front-loaded with the core action and then the key constraints. Every sentence carries useful information, and there is no repetition or 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?

For a tool with nested items, four top-level parameters, and no output schema, the description covers recipient country/state requirements and a sibling-rate caveat. It remains incomplete because the items array is central to the calculation but is never explained. The annotations cover safety, so the main remaining gap is parameter-level completeness.

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%, so the description must carry parameter meaning. It explains country_code and conditional state_code requirements, which is valuable. However, it says nothing about the items array structure, variant identifiers, currency, or locale, leaving key inputs undocumented.

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 states a specific verb and resource: 'Calculate Printful shipping options,' scoped to catalog or warehouse items. It also names the sibling estimate_order_costs and explains a key difference, helping distinguish the two tools. It stops short of a fully explicit routing statement, but the purpose is clear.

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 provides useful requirements for country_code and conditional state_code, and notes that rates can differ from estimate_order_costs when store shipping settings apply. However, it does not explicitly say when to choose this tool over estimate_order_costs or when it should not be used. 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.