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

Annotations already declare readOnlyHint, openWorldHint, and non-destructive behavior, so the safety profile is covered. The description only adds the underlying REST path (GET /suppliers/{id}); it says nothing about not-found behavior or what fields are returned.

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 sentences with the cardinality and identifier requirement front-loaded. The REST endpoint line is slightly redundant but informative for API-oriented agents.

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 single-parameter read tool with full annotation coverage, the description is minimally sufficient. It omits error behavior (e.g., unknown id) and any sense of the returned supplier record, which would help given there is no output schema.

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 itself documents supplier_id as a KiotViet supplier id. The description's 'by id' adds no format or validation detail beyond the schema, so the baseline of 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 resource and cardinality ('one supplier by id'), which lets an agent distinguish it from kiotviet_list_suppliers. The verb is implicit rather than stated, and no sibling is named explicitly.

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?

No guidance on when to use this versus kiotviet_list_suppliers or kiotviet_get_customer_by_code style lookups. The condition 'when you already have the supplier id' is only inferable from the parameter name.

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