get_monthly_usage

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does not state whether the operation is read-only, what the return format is, or any side effects. The cryptic '(year, month, events)' also fails to clarify actual behavior.

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?

The description is a single short sentence, making it concise and front-loaded. However, it is somewhat cryptic and the parenthetical adds ambiguity rather than clarity, so it is not a perfect example.

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?

Given no output schema and no annotations, the description should explain what is returned and how it fits among siblings. It barely does so, and the lack of differentiation from similar tools makes it incomplete for an agent.

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?

Schema description coverage is 100% for both parameters, so the baseline is 3. The description adds no meaningful parameter information and the parenthetical '(year, month, events)' could confuse an agent by suggesting parameters that do not exist.

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 states it returns 'monthly event usage counts for billing/quota', giving a specific resource and purpose. However, the parenthetical '(year, month, events)' is ambiguous and does not correspond to actual parameters, and it does not clearly differentiate from sibling tools like get_metrics or get_periodic_stats.

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?

No guidance is provided on when to use this tool versus alternatives. It does not mention any exclusions, preconditions, or recommended use cases beyond the vague 'for billing/quota'. The description does not help an agent choose between this and similar analytics tools.

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