get_monetization_stats

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

Despite strong annotations (readOnlyHint, idempotentHint, destructiveHint all safe), the description adds meaningful behavioral context: it explicitly confirms no billing state changes and no charges, notes the API key requirement, warns that revenue is in minor currency units unless stated, and clarifies that zero paid subscribers is a valid answer. This is genuinely useful beyond the annotations.

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?

Four sentences, each earning its place: function summary, selection guidance, safety/read-only note, and currency/numeric caveat. No fluff, front-loaded with the core purpose, and efficiently structured.

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 one optional param, no output schema, and rich sibling context, the description fully covers what an agent needs: what the tool returns, when to use it, when not to, read-only behavior, API key requirement, and a data-format caveat. Nothing important is missing for this low-complexity tool.

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 coverage is 100% for the single optional period parameter, so the baseline is 3. The description adds the default ('default 30d' is also in the schema property description) and context that the period affects the trailing window, which the schema property description already covers. However, the description's focus on account-level totals and the inability to break down per campaign effectively frames the meaning of the period, adding semantic value. Slight bonus for clarifying how the parameter relates to the returned figures.

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 clearly states the verb ('Get') and resource ('newsletter monetization figures'), enumerates key metrics (paid subscribers, MRR, churn, revenue trend), and distinguishes itself from get_revenue_attribution. This goes well beyond a paraphrase of the title and gives a precise, specific purpose.

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?

Explicitly tells the agent when to use it ('how is the paid newsletter doing') and provides a concrete exclusion: because figures are account-level and not campaign-breakdownable, use get_revenue_attribution for per-campaign breakdowns. This is the clearest possible guidance for tool selection.

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