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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so no contradiction exists. The description adds useful behavioral context beyond annotations: the result can include hundreds of stores, only current cashback-offer stores are included, and gift-card presence is indicated via specific fields with no rates returned. This goes beyond what annotations alone convey.

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 front-loaded with the core purpose and then provides usage guidance, exclusions, and presentation instructions. It is longer than minimal but each sentence carries information; the final formatting instruction is useful even if slightly beyond selection/invocation needs.

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?

Given the rich input schema, an output schema, and annotations, the description covers scope, limitations, alternatives, country-code handling, and output presentation. There are no significant gaps that would prevent an agent from invoking this tool correctly.

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?

The input schema already fully documents country_code with format, examples, and a pointer to get_countries, so high schema coverage gives a baseline of 3. The description reinforces that a single country is used but does not add substantially new parameter-level meaning beyond the schema.

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 ('Lists') and resource ('every store that currently has cashback offers in one country'), and immediately clarifies what is excluded ('but no rates'). It also distinguishes itself from rate- and gift-card-focused siblings by naming them as alternatives. An agent can tell exactly what this tool does and does not return.

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 explicit when-to-use scenarios with example queries and explicitly warns against using it to find a particular store or its rates, naming the correct sibling tools instead. It also routes the agent to get_countries for supported codes. This is complete usage guidance with both positive and negative selection criteria.

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