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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds useful behavioral context beyond annotations: it names the event source (devdome('event', name) or plugin event tracking) and discloses that output is aggregated to one row per event name with counts for the window.

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, front-loaded with the core purpose and return shape, with the second sentence adding a useful linkage to the event filter. There is no 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?

For a six-parameter tool with nested filters and no output schema, the description gives a basic return-value summary and one parameter linkage, but it omits usage differentiation from siblings and does not explain the window parameters. It is minimally adequate but leaves meaningful gaps.

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?

With only 33% schema description coverage, the description must compensate but largely does not. It does clarify that event names populate the filters.event parameter, but it leaves top-level parameters like site, to, days, and limit unexplained beyond the schema, and it does not define how the window is formed.

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 resource ('Custom events the site sends') and return shape ('one row per event name with counts for the window'), which distinguishes it from generic analytics siblings like get_breakdown or get_stats. It does not explicitly say how it differs from every sibling, but the custom-event focus is clear.

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 notes that 'Event names feed the event filter,' which implies a use case, but it gives no explicit when-to-use guidance, no when-not-to-use guidance, and no alternatives among the many sibling reporting tools. An agent must infer that this is for discovering event names rather than for general traffic reporting.

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