calendar_update_event

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

With no annotations, the description carries the full behavioral burden. It discloses several critical behaviors: partial updates (only passed fields written), attendees replacing the whole list, etag-based conflict detection, and the requirement for confirmSeries on recurring series. This is strong transparency beyond the schema, though it omits details about permissions or error responses.

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 three sentences with no wasted words. It leads with the core purpose, then provides essential behavioral nuances. Each sentence adds critical information, making it both 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 tool with 13 parameters and complex behaviors like partial updates, etag guarding, and series handling, the description covers the essential decision points. It lacks an explicit mention of return values or detailed error conditions, but given the absence of an output schema, this is acceptable. The description is sufficiently complete for an agent to invoke the tool correctly in most scenarios.

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 85%, so the baseline is 3. The description adds valuable semantics: it clarifies that fields not passed are left unchanged, that attendees replaces the entire guest list, and that confirmSeries is required for series. These nuances are not in the schema, enhancing parameter understanding.

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 clearly states the action ('Change fields of an existing event') and specifies the resource and scope, listing exactly which fields are affected. It immediately distinguishes this from creation or deletion of events, making the tool's purpose 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 implies this is for updating existing events, but it does not explicitly contrast it with calendar_create_event or calendar_delete_event. It provides no 'when not to use' guidance, leaving some inference to the agent. However, the main purpose is clear enough to route correctly in most cases.

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