Get Calendar Event

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

Annotations already declare readOnly, idempotent and non-destructive behavior, so the safety profile is covered. The description adds real value beyond them by naming the required scope (calendar.read) and by warning that the returned concurrency token must be retained for a subsequent conditional change, which is non-obvious operational 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 short sentences, front-loaded with the action and its precondition, then the auth requirement, then the follow-up advice. Nothing is redundant or padded.

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?

Returns are covered by the output schema and all three parameters are documented in the schema, so the description only needs to supply usage, auth, and concurrency context, which it does. A note on what happens when the credential spans multiple mailboxes (selecting via mailbox_id) would round it out, but the schema already covers that.

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%, so the baseline is 3, but the description goes further by framing the returned ETag as a 'concurrency token' tied to conditional changes, giving the If-None-Match parameter practical meaning beyond its schema text. It does not explain mailbox_id resolution, but the schema handles that.

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 gives a specific verb and resource ('Read one event'), which clearly separates it from the list siblings such as mailbox_list_calendar_events and the sibling get_calendar_event variants by scoping to a single event. It stops short of naming an alternative tool outright, so it is clear but not fully differentiated in-text.

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?

It states a concrete when-to-use condition: read before editing or deleting. That implicitly routes the agent to mailbox_update_calendar_event and mailbox_delete_calendar_event without naming them, and there is no explicit when-not guidance.

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