calendar_list_recurring_instances

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

With no annotations, the description bears full responsibility for behavioral disclosure. It only states 'list instances' without revealing that the event must be recurring, how time_min/time_max filter results, or whether pagination is returned. This is a significant gap for a read operation with multiple filtering parameters.

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, front-loaded sentence with no extraneous content. It is appropriately concise for a simple listing operation, though it could have expanded on usage without violating conciseness.

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 a tool with 5 parameters and an output schema, a one-sentence description is inadequate. It omits essential context such as the need for a recurring event's ID, the role of time_min/time_max, and the meaning of max_results. The output schema may define return payloads, but operational context remains missing.

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 0%, and the description fails to compensate. Parameter names like event_id and time_max are intuitive, but the description does not clarify their formats, relationships, or defaults. The event_id requirement and optional time filters remain under-explained.

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 uses a specific verb ('List') and resource ('instances of a recurring event'), clearly distinguishing it from siblings like calendar_get_events (which lists events generally). It is unambiguous and directly states the tool's core function.

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. It doesn't mention that event_id must correspond to a recurring event, nor does it contrast with calendar_get_events or calendar_create_event. The description gives no context for appropriate invocation.

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