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

Annotations already declare read-only and idempotent. The description adds valuable behavior: expired codes excluded, daily refresh, and cashback stacking. This goes beyond the annotations without contradicting them, though it does not cover every possible detail (e.g., pagination or exact formatting).

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?

Two sentences, front-loaded with the main purpose, followed by useful boundaries and relationship to cashback. Every sentence earns its place with no redundancy.

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 zero-parameter, no-output-schema tool, the description is complete: it covers what is returned (codes, min spend, qty, expiry), scope (USD site), refresh cadence, exclusions, and stacking behavior. It leaves no significant ambiguity.

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 and the schema is empty, so the description does not need to explain parameters. Per the rubric, baseline is 4 in this case, and the description adds no param-specific info but doesn't need to.

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 uses a specific verb (list) and clearly identifies the resource (active AliExpress promo codes on the global USD site), including types (platform-wide and product-specific) and key attributes (minimum spend, remaining quantity, expiry). This distinguishes it from siblings like get_cashback_link and search_products.

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 gives clear context: active codes, expired excluded, daily refresh, and stacking with cashback. This implies when to use it, but it does not explicitly state when not to use it or name alternative tools, so it falls short of a 5.

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