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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description goes well beyond by disclosing the required auth scope, the no-paging behavior, the per-row outcome semantics, and especially the security-relevant 'untrusted_fields' wrapping. This is valuable behavioral context the annotations do not provide.

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 dense but every sentence earns its place: auth, purpose, row semantics, default window, paging limitation, and result wrapping are all covered. It is front-loaded with the core action and the user-facing question, then moves into supporting details without redundancy.

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 full burden of explaining return shape and delivers with `data` and `untrusted_fields`. It also covers auth requirements, default time window, filtering semantics, and explicitly states the missing paging behavior. The agent has enough to safely invoke and interpret this 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%, so the baseline is 3; the schema already documents limit, status, and monitor. The description adds operational meaning to the status parameter (pending, delivered, dead, suppressed with concrete causes) and explains row granularity, which helps the agent choose filters. It does not add much for limit or monitor, but those are adequately described in the schema.

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 ('List recent alert deliveries across every monitor in the project') and explains the exact diagnostic scenario it answers, including the statuses returned. This clearly differentiates it from siblings like list_destinations and gets the agent pointed at the right tool.

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 an explicit use case ('my monitor went down and I was not paged...') and tells the agent when not to use it: paging is intentionally not exposed, and full archive needs belong to the dashboard's delivery log. This is direct when/when-not guidance without leaving the agent to infer.

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