update_calendar_event

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

No annotations are present, so the description bears full responsibility for behavioral context. 'Update' implies mutation, but no details are given about reversibility, permissions required, or side effects. Notably, the input schema has zero parameters, which is contradictory for an update operation; the description does not clarify this anomaly.

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 a single sentence, which is concise but at the expense of necessary detail. It is under-specification rather than effective conciseness. The agent needs more context to use the tool correctly.

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?

Given the complexity (an update operation with zero parameters and no output schema) and the presence of sibling CRUD tools, the description is severely incomplete. It provides no guidance on how to identify the event, what fields can be updated, or what response to expect. The agent cannot reliably use this tool.

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?

The input schema has zero parameters, and though schema coverage is 100% (trivially), the description adds no explanation for how to specify the event to update or what fields are available. For a zero-parameter tool, a baseline of 4 is warranted if the description compensates, but here it fails to do so, leaving the agent confused about how to invoke the tool.

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?

Description is 'Update an existing calendar event', which is a generic verb+resource but fails to distinguish from sibling tools like create_calendar_event or delete_calendar_event. The name already implies the purpose; the description adds no additional differentiation.

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?

No guidance is provided on when to use this tool versus alternatives (e.g., create or delete). There is no mention of prerequisites such as needing an event identifier or specifying which calendar. The agent has no context to select this tool appropriately.

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