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

Annotations already declare readOnly, idempotent, non-destructive, so the safety profile is covered. The description adds real value beyond that: it enumerates the returned metrics, their units (seconds), the 30-day default window, and the 25-account cap on includeAccounts breakdowns.

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?

Three sentences, front-loaded with the core purpose and metric list, then the optional breakdown, then sibling routing. Every clause adds information; nothing is redundant filler.

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 it does so comprehensively (metric names plus units). Combined with the default window and breakdown cap, an agent has everything needed to call and interpret the result.

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%, so baseline is 3. The description nonetheless clarifies includeAccounts ('adds a per-account breakdown (up to 25)') and the default window, going slightly beyond the schema, but it does not explain platform or workspaceId behavior, which the schema already handles.

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?

States a specific verb ('Measure messaging performance over a window') plus the exact metric set returned (received/sent, automation-answered counts and percentage, conversations, unread, avg/median response time). An agent can distinguish this from generic get_analytics or get_automation_usage without opening the schema.

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 routes to two alternatives: get_automation_usage for per-automation run volume and list_conversations for the conversation objects themselves. It lacks an explicit 'do not use for X' exclusion or prerequisites (e.g., permission requirements), which keeps it just under a 5.

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