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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so safety is covered. The description adds genuine behavioral context beyond them: the underlying REST endpoint, the fact that error text is deliberately excluded, and that results are a delivery log rather than configuration. It does not state the retention window behind 'recent', which is the main remaining gap.

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?

Two sentences, no filler. The core purpose and the heatmap anchor are front-loaded, and the exclusion and endpoint mapping follow as supporting detail.

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 read-only single-parameter list tool with no output schema, the description covers purpose, data provenance, and an explicit content exclusion. It is slightly incomplete in not hinting at the returned fields or the retention window, but nothing needed to invoke it correctly is missing.

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% and the single 'limit' parameter is fully documented (default 100, max 500, most-recent-first ordering), so the schema carries the burden. The description adds nothing parameter-specific, which is the expected baseline 3 when the schema is complete.

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?

Specific verb+resource ('list alert delivery history') with an unusual amount of semantic disambiguation: it explains the data is about whether an alert fired and whether the send succeeded, and pins it to the Alerts page heatmap. This clearly separates it from siblings like list_alert_channels and list_alert_subscriptions, which cover configuration rather than delivery outcomes.

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 frames when the data is relevant (the Alerts page heatmap) and notes a scope boundary ('does not include the delivery error text'), but it never states when to prefer this tool over the alert-config siblings or what to do if error detail is needed. Usage is implied rather than routed.

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