calendar_list_upcoming_events

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds the permission requirement (Calendars.Read) and specifies return fields (id, subject, start/end times, organiser, online status), which goes beyond the annotations and provides useful expectations.

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 carrying distinct value: action and ordering, return fields, and usage guidance with a permission note. No redundancy or filler, making it highly concise 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?

For a simple read-only list tool with two optional parameters and no output schema, the description covers purpose, scope, alternatives, permission, and return fields. It is sufficiently complete for an agent to select and invoke correctly without gaps.

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?

The input schema has 100% description coverage with both parameters (days_ahead, max_results) clearly described. The description adds no new parameter-level details beyond what the schema already provides, so a baseline score of 3 is appropriate.

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 lists the signed-in user's upcoming calendar events for a specified number of days, ordered soonest first. It explicitly distinguishes from siblings by naming calendar_list_events_in_range and calendar_get_event and asserting this is 'the tool for what's on my calendar'.

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?

Provides explicit guidance on when to use this tool vs alternatives: 'Use calendar_list_events_in_range for a specific window, and calendar_get_event for full detail including the join URL.' Also frames the primary use case with 'This is the tool for what's on my calendar'.

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