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

With no annotations provided, the description carries the full burden. It discloses key behaviors: the event is moved (not copied), times are preserved, and guests receive an email update. It does not mention potential failures, permissions, or that the original calendar entry is removed, but these are reasonably implied by 'move'. The side-effect of emailing guests is a valuable disclosure.

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 description is two sentences with no fluff. The primary action is front-loaded, and the side effect is stated second. Every word contributes value, making it highly concise and well-structured.

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 moderate-complexity move operation with no output schema, the description covers the essential context: the action, scope (same account), preservation of times, and guest notification. It does not mention explicit prerequisites (e.g., permissions to the destination calendar) or failure conditions, but these are minor given the simplicity of the operation and the clarity of the purpose.

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 50% (mailbox and calendarId have descriptions, eventId and destinationCalendarId do not). The tool description adds no parameter-specific guidance, so it does not compensate for the undocumented parameters. The parameter names are self-explanatory, but the description offers no additional context, such as why calendarId is optional or how destinationCalendarId should be formatted.

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 ('Move'), a resource ('Google Calendar event'), and the action ('to a different calendar on the same account, keeping its times'). It clearly distinguishes from siblings like update_google_calendar_event (which modifies details) and create/delete tools. The purpose is unambiguous.

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 clearly implies when to use this tool: when an event needs to be moved to a different calendar while preserving times. It also notes that guests are emailed, which is a contextual side effect. However, it does not explicitly name alternatives or state when not to use it, though the inference is straightforward.

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