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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds genuine behavioral context beyond that: it scopes the result to the current billing period and clarifies the counts are used-vs-allowed. It stops short of noting caching, refresh timing, or whether the call itself consumes quota.

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 dense sentence with zero filler; the core purpose is front-loaded and the metric list follows as supporting detail. Nothing in it is redundant with the title.

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?

With no output schema, the description carries the return-value burden, and it does so by enumerating every metric reported (applications, keywords, competitors, inspections, niche analyses, autocomplete queries, metadata simulations, API requests). An agent knows exactly what it will receive without opening a schema.

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 no parameters, so there is nothing to disambiguate and the description correctly adds no parameter guidance. Baseline for a zero-param tool is 4.

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 (Get) and resource (current account usage and plan limits), then enumerates the exact metrics returned. It is cleanly distinguishable from every per-resource sibling like list_applications or inspect_keyword, since it is the only aggregate-usage tool.

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 — call it to check consumption against plan limits for the current billing period — but the description never states when to prefer this over siblings or what triggers a need for it (e.g., before bulk operations or quota errors). No exclusions or alternatives are given, though none are strongly needed for a zero-arg aggregate tool.

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