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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so safety and idempotency are covered. The description adds real value beyond that by disclosing what the response carries: status, DNS and certificate validation results, primary designation, and DNS records to add. It stops short of noting pagination or ordering behavior.

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?

A single tight fragment with the resource front-loaded and the returned fields enumerated without filler. The lack of a verb makes it read as a label rather than a full statement, but nothing is wasted.

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?

A one-parameter, read-only listing tool with no output schema; the description compensates by summarizing the returned fields (status, DNS/cert checks, primary flag, DNS records), which is most of what an agent needs to interpret results. No note on empty-state or multi-domain ordering, hence not a 5.

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?

Only one parameter exists and schema description coverage is 100% (productId documented as 'Product id from list_products'). The phrase 'a hosted product's' loosely ties the listing to productId, but adds no syntax or format detail beyond the schema, so 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?

The description names the resource precisely (a hosted product's custom help center domains) and enumerates what is surfaced, so the agent knows this is a listing/read of domain configuration. It does not explicitly differentiate itself from nearby siblings like check_help_center_domain or set_primary_help_center_domain, but the resource scope is clear.

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?

There is no when-to-use guidance, no prerequisites, and no routing to alternatives such as check_help_center_domain (single-domain inspection) or add_help_center_domain. Usage is only inferable from the name and the fields it returns.

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