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

Annotations already cover readOnly/idempotent/destructive/openWorld, and the description adds genuinely non-redundant behavior: quota accounting ('each ID consumes one normal catalog quota unit', charged even for missing products), partial-failure semantics via missing_ids for unpublished or absent products, and ordering guarantees. Those are exactly the operational details annotations cannot express.

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?

Four tight sentences, front-loaded with the core action and count limits, then return semantics, then cost, then access constraints. No filler and no repetition of the tool name as an explanation.

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?

With an output schema present, return values need not be documented, yet the description still communicates ordering and missing_ids. Combined with the quota cost model, authentication posture, and input restrictions, an agent has everything needed to batch-call this correctly.

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 single parameter is fully documented, including the ID-vs-SKU distinction and the quota note. The description restates the same facts ('unique', '1 to 10', 'internal ID', quota per ID) rather than adding new semantics, so the 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 and resource with batch scope ('Read 1 to 10 unique products by internal ID') and also discloses the return shape (requested order, missing_ids). The batch/ID-based framing implicitly separates it from get_product and search_products, but no sibling is named explicitly, so it falls just short of the top band.

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?

Gives clear operating context: public, no OAuth required, and explicit exclusions ('no URLs, buyer actions or writes are accepted'), which tells the agent what inputs will fail. It stops short of naming the alternative path (e.g., use search_products to obtain IDs), leaving that inference to the reader.

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