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

The description goes beyond the annotations by disclosing a concrete side effect: it writes the city into the cart address. It also states the OAuth requirement, which is not present in the annotations. It stops short of describing output, rate limits, or failure behavior, so it is not a 5.

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?

The description is three short sentences with no filler. It front-loads the purpose, then adds the side effect and auth requirement in logical order, making it easy to scan.

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?

The description is sufficient for making a basic call with required parameters, but there is no output schema and the description never says what the tool returns, how to interpret the estimate, or how postal_code influences the result. That leaves a meaningful gap for an agent deciding whether the response satisfies the request.

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?

With 0% schema description coverage, the description must compensate for parameter meaning. It clarifies that cart_id refers to the cart being evaluated and city is the delivery destination, but the optional postal_code parameter is completely unexplained. The agent gets no guidance on its format, purpose, or effect.

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 action—estimating delivery for a cart to a city—and names concrete delivery modes: pickup, store delivery, and transport-company tariffs. This clearly differentiates it from sibling tools like create_invoice_order or build_cart.

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 intended use case is implied: call this when a delivery estimate for a cart to a city is needed. However, there are no explicit when-not-to-use instructions or named alternatives, so the agent is left to infer routing from sibling names.

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