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

Annotations already declare readOnly, openWorld and non-destructive, so the safety profile is covered. The description adds real value by disclosing the endpoint (GET /categories/{id}) and the shape of the returned record (name, parent, children), though with no output schema, error/not-found behavior and whether children are full sub-trees or ids remain unstated.

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, zero waste, with the core identity of the tool front-loaded before the endpoint detail. Nothing could be removed without losing information.

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 tool whose annotations carry the safety profile, this is nearly complete: it says what is fetched and what fields come back. Minor gaps are the absence of any not-found/error note, which matters for an open-world API read.

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 parameter and schema description coverage is 100% ('KiotViet category id.' with positive-integer bounds). The description's 'by id' restates rather than extends the schema, so the baseline 3 applies — no format, sourcing, or lookup guidance beyond it.

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-resource pair ('One product category by id') and scopes it to a single record, which separates it from the sibling kiotviet_list_categories without naming it. The parenthetical return fields add precision about what a category record contains.

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 'by id' — an agent can infer this is the single-record lookup versus the list tool, but nothing states prerequisites, when to prefer it over the list variant, or what to do if the id is unknown.

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