Read the Alza account cart

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the read-only nature is covered. The description adds valuable context: it requires a loaded mobile API access token and gives a fallback sequence, and it notes the response envelope is large with specific signal fields. This goes beyond annotations without contradicting them.

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 thorough yet efficient, with no filler. It front-loads purpose, then usage and exclusions, then auth prerequisites, and ends with a useful response-size hint. Every sentence earns its place, and it remains compact given the scope.

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 no parameters, an output schema, and comprehensive annotations, the description is remarkably complete. It covers purpose, use cases, alternatives, auth prerequisites, and response guidance. Nothing an agent needs to call it correctly is missing.

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?

There are zero parameters, so the schema has nothing to explain and the description carries no parameter burden. The baseline of 4 for zero-parameter tools is appropriate, and the description does not need to elaborate further.

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 ('Read') and resource ('authenticated user's Alza shopping cart') and enumerates the key contents (item lines, discounts, vouchers, identifiers). Explicitly distinguishes from the sibling `web_cart` for anonymous carts, so an agent can tell them apart without opening schemas.

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?

Gives explicit when-to-use scenarios (verify add_to_cart, inspect coupon state, collect ids for mutate_list) and an explicit when-not-to-use with the named alternative (`web_cart`). Also explains prerequisite auth steps via `account_status`/`auth_start`/`auth_exchange`, which is strong routing guidance.

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