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

With no annotations, the description carries the full burden of behavioral disclosure. It discloses the underlying endpoint, the v2 API caveat, and the response shape (per-day rows plus a computed totals+rates roll-up). It does not mention pagination or date-boundary behavior, but these are minor for a read-only analytics tool.

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 efficiently structured with a front-loaded summary, followed by a relevant endpoint note and a concise description of the return value. Every sentence adds useful information without fluff.

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?

For a simple, two-optional-parameter tool with no output schema, the description covers the endpoint, aggregation scope, and response structure. It is slightly incomplete around date parameter format and metric definitions, but overall adequate for correct invocation.

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 0%, and the description does not explain start_date or end_date semantics, date format, or inclusive bounds. The parameter names are somewhat self-explanatory, but the description does not compensate for the lack of schema-level parameter documentation.

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 a specific verb and resource: workspace-level daily sending analytics aggregated across accounts. This clearly distinguishes it from campaign-specific siblings like get_campaign_analytics. The note about the underlying endpoint reinforces the exact scope.

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?

The description provides clear context for when to use this tool: for workspace-level analytics, not account- or campaign-level analytics. It does not explicitly name alternatives or state when not to use it, but the scope is clear enough to guide selection.

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