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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds that exactly one product is returned (singular, no pagination) and names the underlying endpoint, but says nothing about behavior when the code does not exist or about auth failures. Modest value on top of annotations.

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 short fragments with zero padding, and the identifying concept (one product by code) comes first. The telegraphic phrasing ('One product by its product code... GET /products/code/{code}.') is terse to the point of being sentence fragments, which costs it a point.

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 one-parameter read lookup with annotations and a fully documented schema, the core need is covered. But there is no output schema, and the description does not describe the returned product shape or the not-found behavior, which is the main remaining gap for an agent.

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% and the single parameter 'code' is already documented in the schema with length bounds. The description's '(SKU)' adds a small synonym hint but no format, case-sensitivity, or example beyond the schema. 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-less but unambiguous purpose: retrieve one product identified by its product code (SKU). The '(SKU)' gloss clarifies the key type, which implicitly separates it from kiotviet_get_product (by id) and kiotviet_list_products. It never names a sibling explicitly, so differentiation is left to inference.

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 only implied: 'by its product code (SKU)' suggests this is the lookup to use when you hold a code rather than an internal id. There is no explicit when-to-use/when-not, no pointer to kiotviet_get_product or kiotviet_list_products as alternatives.

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