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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds useful context by listing returned fields and the underlying GET endpoint, but it says nothing about authentication, error cases, or how missing IDs are handled.

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 definition is a single front-loaded sentence followed by the endpoint, with no wasted preamble. The trailing "..." and "..." style is slightly informal, but the content is appropriately sized for a simple lookup tool.

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 one-parameter read-only lookup with full schema coverage and annotations, the description is reasonably complete: it states the resource, required identifier, returned fields, and endpoint. The absence of an output schema is partly compensated by the field list, though it remains non-exhaustive.

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 description coverage is 100%, and the schema itself explains that event_id may be an Evenium id or an `ext:<your own event id>` value. The description adds no meaningful parameter semantics beyond "by id", so the baseline 3 is appropriate.

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+resource ("Get one event by id") and enumerates the returned fields (title, description, dates, status, site path, fields), which clearly distinguishes it from list-oriented siblings such as evenium_list_events. However, it does not explicitly name a sibling alternative the way a 5 would.

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 phrase "One event by id" implies a single-record lookup, so an agent can infer this is the right tool when an event id is known. But there is no explicit when-to-use/when-not guidance and no mention of alternatives like evenium_list_events for browsing.

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