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

Description adds real value: the timezone-of-start_date rule, all-day option, and return shape ({ EventId }). But annotations declare destructiveHint=true — plausible for calendar mutation since it can add attendees/notify — yet the description never discloses any destructive/notification/permission behavior. That gap holds it to 3; there's no contradiction, just silence on the annotated risk.

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 tight sentences, all load-bearing: capability, timezone behavior, return value, plus alias. Front-loaded and no redundancy.

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 an 8-parameter mutation tool with no output schema, the description covers the essentials an agent needs (trigger, timezone rule, return). It leaves attendees/calendar_id defaults and destructive side-effects to the schema and annotations, which is acceptable given 75% coverage.

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 75%, so most parameters are self-documenting. The description echoes 'attendees' and 'all-day' implicitly but adds no syntax or constraint detail beyond the schema (e.g. no required-field reminder, no calendar_id default emphasis) to compensate for the 25% gap.

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?

States a specific verb+resource ('Create a timed (or all-day) event on your calendar') with scope qualifiers (attendees optional). Distinguishes cleanly from sibling lacrm_list_events, which is the read counterpart.

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?

Implicitly the tool for scheduling new events, but no explicit when-to-use guidance or routing vs alternatives (e.g. lacrm_list_events to check availability). Timezone behavior is mentioned but not framed as a usage decision.

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