List calendar events

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

Annotations already declare this read-only, idempotent, and non-destructive. The description adds valuable behavioral context beyond those hints: recurrence expansion, cross-account merging and sorting, and the explicit UTC-offset requirement for timestamps. It does not contradict any annotation.

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 sentences, each earning its place: the core action, the cross-account behavior, and the two critical gotchas (recurrence expansion and UTC offsets). The most important behavioral details are front-loaded and there is no redundant filler.

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 read-only listing tool with 100% schema coverage and helpful annotations, the description covers the essential operational nuances an agent needs: time-range usage, account omission behavior, recurrence handling, and timestamp format requirements. The absence of an output schema is mitigated by the clear 'list events' framing.

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 baseline is 3. The description mostly reinforces what the schema already says about 'account' and time parameters, though it adds the merged-and-sorted behavior and the recurrence-expansion detail. This is useful but does not substantially enhance parameter-level meaning 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 states a specific verb and resource: 'List events in a time range,' with concrete behavioral details like merging all calendars, sorting by start time, and expanding repeating events. This clearly distinguishes it from sibling tools such as calendar_get_event, which targets a single event, and calendar_find_free_time, which searches availability.

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 gives clear contextual usage guidance: it explains how to query across every connected calendar by omitting 'account' and emphasizes the required time-range format with UTC offsets. It does not explicitly name alternatives or exclusion conditions, so it stops short of a full when-to-use versus when-not-to-use guide.

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