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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the aggregation windows (24h/7d/30d) and the count categories, which is useful scope context, but says nothing about cost, caching, or behavior for unknown domains.

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?

One front-loaded sentence with no filler; the enumeration is long but each item is a distinct returned metric that earns its place.

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 the return format need not be explained, and the read-only annotations cover the safety story. The remaining gap is the unclear input format for 'domain', which is minor for a simple aggregation endpoint.

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 0% for the single 'domain' parameter, so the burden falls on the description, which only repeats the word 'domain'. It does not specify the expected format (bare hostname vs. URL vs. subdomain handling) or whether wildcards are accepted.

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 scan counts for a domain') and enumerates the exact metrics returned, which separates it from list-oriented siblings like get_domain_scans and get_domain_history. It stops short of explicitly naming those alternatives, so a 4 rather than a 5.

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 mention of prerequisites, and no routing to alternatives such as get_domain_scans for the underlying scan list. The agent must infer from the sibling names alone.

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