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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false), so the description's contribution is the scope note that codes come from the site's own connected Stripe account, plus 'on or off' implying both active and inactive codes are returned. It omits ordering, pagination, and empty-state or disconnected-Stripe behavior.

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?

A single compact sentence that front-loads the resource and its source before the field list. Nothing extraneous, though the terse fragment style slightly reduces readability.

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 one required parameter and no output schema, enumerating the returned fields is genuinely helpful and largely fills the gap. However, a list operation with an external dependency (Stripe) should at least note what happens when the account is not connected or when no codes exist.

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 100% for the single required siteId parameter, so baseline is 3. The description only refers to 'the site's' codes and adds no format, default, or scoping detail beyond what the schema already states.

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 names a specific resource (promo codes) with a clear scope (the site's own Stripe account) and enumerates the fields returned, so an agent knows exactly what it is retrieving. It does not explicitly contrast with the sibling set_promo_code, but the list-vs-set distinction is obvious from the verb and title.

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?

There is no explicit when-to-use guidance, no mention of a prerequisite Stripe connection requirement (only an oblique 'from its own Stripe account'), and no named alternative such as stripe_get_product or set_promo_code. The usage is only inferable from the tool name.

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