calendar_find_free_time

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions analyzing 'existing events' and returning 'free gaps,' which gives some context about what the tool does, but it lacks details on permissions needed, rate limits, whether it accesses multiple calendars by default, or how it handles overlapping events. For a tool with no annotation coverage, this leaves significant behavioral aspects unclear.

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 appropriately sized and front-loaded: it starts with the core purpose ('Find available time slots...'), followed by a clarifying sentence ('Analyzes existing events...'). Both sentences earn their place by adding value without redundancy, making it efficient 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?

Given the tool's moderate complexity (5 parameters, no output schema, no annotations), the description is somewhat complete but has gaps. It explains the high-level function but lacks details on behavioral aspects like error handling or output format. Without annotations or an output schema, the description should do more to cover these areas, making it adequate but not fully comprehensive for the context.

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 100%, meaning all parameters are documented in the schema. The description doesn't add any specific parameter details beyond what's in the schema (e.g., it doesn't explain the format of 'date' or constraints on 'duration' beyond the schema's '15-480'). With high schema coverage, the baseline is 3, as the description doesn't compensate with extra semantic value, but it also doesn't detract.

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 tool's purpose: 'Find available time slots in your calendar for scheduling meetings.' It specifies the verb ('find') and resource ('available time slots'), and distinguishes it from sibling calendar tools like 'calendar_list_events' by focusing on free time analysis rather than event listing. However, it doesn't explicitly differentiate from non-calendar siblings like 'notes_search' or 'reminders_add', which is why it's not a perfect 5.

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 usage context by stating it 'analyzes existing events and returns free gaps,' suggesting it should be used when looking for open slots in a calendar. However, it doesn't provide explicit guidance on when to use this tool versus alternatives like 'calendar_list_events' for viewing events or 'calendar_create_event' for scheduling, nor does it mention any exclusions or prerequisites. The guidance is present but not comprehensive.

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