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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description adds genuinely non-obvious context beyond the annotations: the authentication requirement and the fact that each call consumes 1 record — a real side effect on the quota being reported.

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, zero waste. The purpose and returned fields are front-loaded, followed by the auth and cost caveats. Every clause 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?

With no output schema, the description compensates by enumerating what the caller gets back (plan, limit, used, remaining, reset time). Auth requirements and the per-call cost are also disclosed, which is everything an agent needs for this trivial zero-param read.

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 by baseline this scores 4. There are no parameter semantics to document, and the description correctly spends its words on output content and prerequisites instead.

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?

The description names the exact resource ('your account's quota position') and enumerates the specific fields returned (plan, monthly limit, records used, remaining, reset timing). No sibling tool (describe_table, query_table, get_record, etc.) covers quota, so the differentiation is unambiguous.

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?

It states the precondition for calling it (a stat-api sign-in or API key) and the cost (1 record), which is useful operational context. However, it gives no explicit when-to-use or when-not-to-use guidance, which is only weakly implied by the tool's uniqueness among siblings.

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