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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is fully covered elsewhere. The description contributes the payload shape (the set of returned fields), which is genuinely useful since no output schema exists, but says nothing about failure modes for an unknown or unauthorized event_id.

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?

One compact sentence fragment, front-loaded with the key qualifier "Full event" and no filler. It is a noun phrase rather than a sentence, which is the main structural weakness.

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 field enumeration is exactly the missing piece an agent needs to know what a successful call yields. Only the error/not-found behavior and the distinction from list_events remain unaddressed.

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 single parameter's schema text already explains that the ID comes from list_events. The description adds no format, provenance, or fallback information beyond that, so baseline 3 applies.

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?

"Full event: ..." signals a single-record detail fetch and enumerates exactly which fields come back, which implicitly separates it from the summary-oriented list_events sibling. It never states an explicit verb ("retrieve"/"fetch") or scope, so the purpose is inferable rather than declared.

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 statement of when to call this versus list_events, list_guests, or update_event, and no prerequisites. The only routing hint lives in the schema ("event_id from list_events"), not in the description.

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