mcp-calendly

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

Annotations indicate readOnlyHint=true, which the description aligns with by using 'Get' (implying a read operation). The description adds minimal behavioral context beyond annotations, such as specifying it returns 'time slots' but not detailing format, pagination, or rate limits. With annotations covering safety, it meets baseline but lacks rich disclosure.

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, efficient sentence with zero waste. It is front-loaded with the core purpose and appropriately sized for the tool's complexity, making it easy to parse quickly.

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 has annotations (readOnlyHint) and high schema coverage, the description is minimally adequate. However, with no output schema, it does not explain return values like slot format or error cases, and it lacks context on usage relative to siblings. For a read operation with three parameters, it could be more complete but meets basic needs.

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%, so the schema fully documents the three parameters (event_type_uri, start_time, end_time). The description adds no additional meaning beyond implying these are used to 'check availability', which is already inferred from the tool name and schema. Baseline 3 is appropriate as the schema handles the heavy lifting.

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 'Get' and the resource 'available time slots for an event type', making the purpose specific and understandable. However, it does not explicitly differentiate from sibling tools like 'list_scheduled_events' or 'list_event_types', which might also involve time-related queries, so it misses full sibling distinction.

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 provides no guidance on when to use this tool versus alternatives. It lacks context on prerequisites, such as needing a valid event type URI, and does not mention when-not scenarios or direct comparisons to siblings like 'list_scheduled_events' for checking existing events versus availability.

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