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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so the safety profile is covered. The description adds nothing behavioral beyond that: no pagination, no result-size limits, and no explanation of what the two named data sources ('canonical deal facets' vs 'promotion store directory') contribute or whether they can diverge.

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 front-loaded sentence with the verb and resource first, so it is efficient and not padded. The wordy internal source phrase costs it a bit of crispness but the sentence still earns its place.

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 read-only listing tool with no output schema, the description should at least indicate what a returned store looks like or how results are scoped/limited. It mentions two data sources without explaining their relationship or limits, leaving the agent unable to predict output or coverage.

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 is a single optional 'country' parameter with 100% schema description coverage including a pattern and example, so the schema fully carries parameter meaning. The description adds no syntax, default, or behavior detail beyond what the schema already provides, which matches the baseline of 3.

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 clear verb (List) and resource (stores), so the basic purpose is legible. However, the qualifier 'from canonical deal facets and promotion store directory' is internal jargon that does not help an agent distinguish this from the sibling get_store_offers, which also returns store-related data.

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 guidance on when to call list_stores versus get_store_offers, search_deals, or get_best_deals. The agent must infer usage purely from the name and the vague source phrase, with no stated exclusions or prerequisites.

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