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

Annotations already declare read-only, idempotent and non-destructive, so the safety profile is covered. The description adds genuinely new behavioral context that annotations cannot express: the call is free and consumes no credits, which matters in a metered API. It stops short of saying whether limits are cached or live.

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 of the three sentences say the same thing ('Free. Free: costs no credits.'), which is pure repetition and eats space that could have carried usage guidance. The remaining sentence is dense but front-loaded with the returned fields rather than a verb, so it reads as a label.

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 burden of describing return values and does so adequately by listing the three quota categories. Since the tool has no inputs and a simple non-destructive read profile, there is little else an agent needs before calling it.

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 per the baseline this scores 4; there is nothing for the description to disambiguate. The description correctly implies no input is required.

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 enumerates the concrete ceilings returned (requests per minute, monitor/webhook counts, hourly-run eligibility), which is a specific resource with identifiable content. It implicitly distinguishes itself from get_identity and get_usage by naming plan-quota data, though it never states that distinction explicitly.

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 statement of when to call this versus the similar account-state siblings get_identity and get_usage, nor any prerequisites. The agent must infer that this is the tier-quota check from the field list alone.

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