get_usage

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

With readOnlyHint=true already covering the safety profile, the description adds real value by disclosing the shape of the response (plan, send limit, domain/contact limits, today's accepted count, billing period). It does not mention auth requirements, rate limits, or how quota exhaustion is represented, so it is not fully transparent.

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: purpose and usage trigger first, then a compact colon-list of returned fields. No filler and nothing redundant.

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 the return payload and does so by enumerating the key fields. It is nearly complete, though it omits units/format nuance (e.g., whether limits are per-day or per-month) and any error or empty-state behavior.

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 baseline is 4. The description correctly implies a parameterless, whole-team query rather than a scoped lookup.

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 a specific resource (the team's plan and quota picture) and enumerates the concrete fields returned: effective plan, send limit, domain and contact limits, emails accepted today, and billing period. It is clearly distinct from analytics-style siblings like get_email_insights or get_deliverability, though it does not explicitly say so.

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 gives a clear usage context — fetch this 'before bulk work' — which tells the agent the practical trigger for calling it. It stops short of naming alternatives or when-not-to-use conditions, so it is strong but not exhaustive.

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