list-events

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

Annotations already declare readOnlyHint=true, and the description reinforces that with 'read-only' at no cost. More importantly, it adds beyond annotations: the no-filter behavior, the UTC canonical representation, and the timezone override via OUTLOOK_DEFAULT_TIMEZONE. This gives an agent a clear mental model of the tool's behavior and return semantics.

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 front-loaded with the primary purpose in the first sentence, followed by usage guidance and timezone semantics in the next two sentences. Every sentence carries actionable information with no filler. The structure is efficient and well-organized.

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 a single optional parameter and no output schema, the description covers everything an agent needs: what it returns, how to limit results, what it does not do, and how timezone is handled. There is no output schema, so the return-field listing is especially valuable. The description is fully self-contained for selection and invocation.

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 already describes count with default and max, so schema coverage is 100%. The description adds meaningful context by calling it 'page size' and clarifying that the tool does not filter, which helps the agent understand the parameter's effect beyond the schema. Since the schema does the heavy lifting, a score above baseline is earned by the added page-size interpretation.

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 opens with a specific verb-resource pair: 'List upcoming calendar events for the signed-in user (read-only).' It clearly differentiates from sibling tools like create-event and manage-event by framing the operation as a read-only list. It also enumerates the return fields (id, subject, start/end, etc.), which resolves any ambiguity about what the tool produces.

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 explicitly states how to control page size with count and gives a direct exclusion: 'this tool does not filter — use the Outlook UI or specific date ranges via Graph for filtered queries.' This tells the agent when to use the tool and when to seek alternatives, which is exactly what usage guidance should do.

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