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

Annotations already establish readOnlyHint=true, so the safety profile is covered. The description adds the pagination contract (next_offset recycled as offset) and the underlying endpoint 'GET /v1/unit', which is useful behavioral context, but it says nothing about ordering, default page size behavior, or what the payload contains.

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, zero filler, with the resource identity front-loaded and the pagination caveat immediately after. Every clause carries 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?

No output schema exists, yet the description notes that ids accompany each unit, and pagination is explained, which covers the main gaps for a filtered list tool. It stops short of describing additional returned fields or result ordering, a minor omission for a low-complexity 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?

Schema description coverage is 100%: limit, match, offset, plural, and singular are all documented in the schema, including the enum semantics and wildcard rules. The description adds only the next_offset/offset linkage, which is already restated in the offset field description, so baseline 3 is correct.

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 and resource ('List product units') and even gives concrete examples (piece, hour) plus the returned key ('with their ids'). It implicitly distinguishes itself from siblings like list_products and list_product_groups, but never explicitly contrasts them.

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 only usage instruction is procedural pagination guidance ('Paged: pass next_offset as offset'). There is no statement of when to call this versus list_products/list_product_groups or any prerequisite conditions, so usage is implied rather than explained.

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