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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so safety behavior is covered. The description adds useful content scope (what fields are returned: indexes, sitemaps, URL counts, problems), which is real value beyond the annotations, but nothing about freshness, empty-result behavior, or auth needs.

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 compact sentences front-loaded with the purpose, then the return scope, then a doc link. Little waste; slightly more enumeration than strictly necessary.

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?

Output schema exists, so return values needn't be re-explained, and annotations cover the safety profile. For a single-param read tool the description is essentially complete; only cross-tool routing guidance is absent.

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's meaning is fully documented in the schema. The description adds nothing about the monitor_id parameter beyond context, 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?

States a specific verb+resource (get sitemap check results for a monitor) and enumerates what the results contain: sitemap indexes, sitemaps, URL counts, problems. Clear, though it doesn't differentiate itself from similar check-result siblings like get_broken_links or get_crawl_results beyond the resource name.

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?

Usage is implied by the name and description (fetch sitemap results for a monitor), but there's no explicit when-to-use vs. alternatives like get_check_summary or get_broken_links. Acceptable for a narrow read tool.

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