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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful context that the index path is fixed and that results include 'inferred types', but does not add much beyond that, making 3 appropriate.

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 sentences, front-loaded with the primary action and immediately followed by the routing alternative. No filler or redundant restatement of the name.

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?

An output schema exists, so return-value details are not the description's burden. The description covers what the tool lists, its sibling relationship, and the input situation, leaving only minor ambiguity around the exact meaning of 'inferred types'.

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?

The tool takes zero parameters, so the baseline is 4. The description reinforces this by noting that no storefront URL input is needed, which aligns with the empty schema and prevents an agent from searching for a missing input.

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 ('List') and a well-defined resource (child sitemap directory and inferred types from the fixed /sitemap.xml index). It explicitly distinguishes itself from its nearest sibling, pristine_marketplace_sitemap_urls, so an agent can route correctly without opening either schema.

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?

Explicitly names the alternative ('Use pristine_marketplace_sitemap_urls to list URLs within one child sitemap') and the condition that selects it, plus clarifies no storefront URL input is needed. It stops short of stating explicit when-not conditions, so it is strong but not fully exhaustive.

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