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

Annotations already declare readOnlyHint=true, so safety is covered. The description goes beyond that by disclosing the content of the result (name, parent, product ids, images) and mapping to the underlying REST endpoint GET /categories/{categoryId}, which is useful for an agent with no output schema.

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, front-loaded with the core action and ending with the REST mapping. No filler or redundancy; every clause 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 single-parameter read tool with readOnlyHint and no output schema, the description covers what is fetched and where it maps in the API. Missing only error/not-found or id-sourcing notes that 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 description coverage is 100% with a single required parameter ('Category id.'), so the schema carries the load. The description adds no syntax, format, or id-sourcing guidance beyond the schema, making the baseline 3 appropriate.

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 with scope qualifiers: 'Get a single category by id', and enumerates the returned fields (name, parent, product ids, images). This clearly separates it from the sibling ecwid_list_categories, which returns many rather than one.

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?

The phrase 'a single category by id' implies the lookup case and implicitly contrasts with the list sibling, but the description never states when to use this versus ecwid_list_categories or what happens for a missing/invalid id. Usage is inferable rather than stated.

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