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

Annotations already indicate read-only, idempotent, non-destructive behavior. The description adds value by specifying the types of metrics (delivery, failure, duplicate, open-issue) beyond what annotations provide, though it does not mention rate limits or authentication details beyond stating 'Authenticated'.

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 extremely concise (7 words, one sentence), which is efficient. However, it omits critical information about parameters and usage, so conciseness comes at the cost of completeness.

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 the single parameter and no output schema, the description does not sufficiently explain input requirements (windowHours) or output format. While annotations provide safety context, the description lacks details needed 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?

The schema has one parameter (windowHours) with no description, and the tool description does not explain its purpose, usage, or impact. With 0% schema description coverage, the description fails to compensate, leaving the agent uninformed.

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?

Description clearly states it provides rollups for delivery, failure, duplicate, and open-issue metrics, distinguishing it from sibling tools that list individual items. However, 'rollups' is somewhat vague and does not specify the format (e.g., counts, averages).

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 on when to use this tool versus sibling tools like list_open_issues or list_delivery_attempts. It does not provide context or alternatives, leaving the agent to infer usage.

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