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

The annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=true, and idempotentHint=false, so the safety profile is covered elsewhere. The description adds nothing beyond that: no mention of pagination, result ordering, result shape, or what an 'event report' object contains. It does not contradict the annotations, but it contributes zero behavioral context.

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 words are technically waste-free, but this is under-specification rather than conciseness. The brevity leaves the agent with nothing to act on beyond the name, and there is no front-loaded scope statement or routing hint.

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?

No output schema exists, so the description was the only place to say what a returned event report looks like or how the list is bounded. Combined with no parameters and heavy sibling overlap, the definition is too thin for an agent to invoke this tool confidently rather than a neighbor.

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 tool takes no parameters (empty object schema at 100% coverage), so there is no parameter semantics for the description to explain. Baseline 4 applies because this dimension cannot be improved by the description given the parameterless design.

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 is a restatement of the tool name: 'List event reports' names a resource and a verb but adds no scope, no filters, and no distinction from siblings like list_reports, get_event_report, or list_event_types. An agent cannot tell from this text what kind of event reports are listed or how they differ from the other report-listing tools.

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?

There is no when-to-use guidance, no exclusions, and no naming of alternatives, despite a crowded sibling set that includes list_reports, get_event_report, create_report, and several other list_*_reports tools. The agent is left entirely to guess which report-listing tool to pick.

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