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

Annotations already mark the tool as read-only and non-destructive, and the description adds meaningful behavioral context: active promotions are returned by default, active=false changes that behavior, and cursor pagination via 'after' is available. This goes beyond the structured 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?

Two concise sentences deliver the core purpose, filtering capabilities, pagination mechanism, and the key default behavior. The most important information is front-loaded, and every clause earns its place without 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 search tool with 11 well-documented parameters, the description captures the essential context: what is searched, what filters exist, how pagination works, and the active-status default. There is no output schema, so the description could have mentioned the response shape more explicitly, but the schema's pagination-cursor reference partially covers that gap.

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 100%, so every parameter is already documented. The description adds a useful high-level summary of the filtering and pagination behavior, but it does not need to restate parameter-level details. This is the appropriate baseline when the schema carries the full semantic load.

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 verb ('Search') and resource ('promotions, coupons, sales, and deals aggregated across retailers'), which makes the tool's purpose immediately clear. It also signals that this is a cross-retailer promotion search, distinguishing it from sibling tools like search_retailer_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?

The description clearly states what the tool searches and lists the main filtering dimensions (retailer, category, promotion type, coupon availability, expiry). It also explains the default active-only behavior and how to opt into expired/upcoming promotions, giving a clear context for use, though it does not explicitly name alternative tools or when not to use it.

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