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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and reach profile is covered. The description adds useful content context, noting the result includes recurring open hours per order channel, but does not discuss rate limits, auth, or resolution 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 tight sentence with the identity of the tool front-loaded and the extra payload detail trailing. No filler.

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 an output schema present, the description need not explain return values, and one fully documented parameter plus clear annotations cover the rest. It is nearly complete, though a one-line note on the invalid/unknown store-number case would round it out.

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% and the schema field itself explains the store_number format ('alphanumeric') and where to obtain it (from /kfc/stores or /kfc/nearby). The description adds nothing parametric beyond that, so the baseline 3 applies.

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 specific verb (looked up) and resource (one KFC restaurant) plus the identifier (store number), which cleanly separates it from list-style siblings like kfc_stores. It does not name a sibling explicitly, so it stops just short of full differentiation.

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?

Usage is implied by 'looked up directly by its store number', signaling this is the by-ID lookup path. However, there is no explicit when-to-use-vs-when-not guidance and no mention of kfc_stores or kfc_nearby as the alternatives for listing or location search.

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