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

Annotations already declare the full safety profile (readOnly, idempotent, non-destructive, closed-world), so little burden remains. The description adds no context beyond the annotations — no caching/freshness behavior, no auth needs — but it does not contradict them either.

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 front-loaded sentence with zero filler; the scope ('directory-wide') comes first and the enumerated metrics follow immediately.

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?

For a parameterless, read-only aggregate tool with a rich annotation set and an output schema covering the return values, the description is essentially complete. It does not explain how the metrics are scoped or computed, but nothing required to call it correctly is missing.

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?

Zero parameters, so the schema imposes no semantic burden and the baseline is 4. Nothing in the description adds or detracts from parameter meaning.

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: 'Directory-wide counts for Agent Web Map,' and enumerates the exact metrics returned. The word 'directory-wide' implicitly separates it from the sibling site_stats, though it never names that alternative.

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 only implied by the 'directory-wide' scope — an agent can infer this is the aggregate-overview call, but the description gives no explicit when-to-use, no guidance on how it differs from site_stats, and no prerequisites.

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