Update iCloud Event

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

Annotations indicate idempotentHint=true and destructiveHint=false, which are consistent with the description stating 'Update fields' and 'only provided fields are updated'. The description adds value by clarifying partial updates and the confirmation response, going beyond the annotation signals.

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 concise (few sentences) and front-loaded with the main purpose. Each sentence provides necessary information: action, parameters, and returns. No redundant information is present.

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?

The description covers the main purpose, parameters, and return value. However, it lacks details on error handling (e.g., event not found), date format expectations (though implied by schema), and behavior when allDay is used with start/end. For a tool with no output schema, more completeness could be beneficial.

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 low (25%), but the description compensates by listing all optional updatable parameters (summary, description, location, start, end, allDay) and explaining that calendar can be a display name or full URL. It also clarifies that uid comes from icloud_list_events, adding context beyond the schema.

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 verb 'Update' and the resource 'an existing event by UID'. It distinguishes from sibling tools like icloud_create_event and icloud_delete_event by specifying the update action on an existing event, avoiding confusion.

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 implicitly conveys when to use the tool (to update an event) and hints at workflow (UID from icloud_list_events), but it does not explicitly state when not to use it or compare to alternatives like icloud_create_event for creating events. No exclusion criteria are provided.

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