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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond that: repeating events expand per occurrence, the default window logic, and the pagination contract (limit per page, total and has_more, pass page for the next). It does not discuss ordering or what date fields the entries carry, but the added context is real.

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 short sentences, front-loaded with purpose and followed by default behavior and return/pagination shape. No filler; each sentence carries information. Slightly dense with parenthetical asides, but nothing is wasted.

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?

With an output schema present, the description need not enumerate return fields, and it still summarizes the pagination envelope. Annotations cover safety. For a 5-parameter, zero-required listing tool the definition is nearly complete; the gap is how explicit date bounds override the default window and the sort order of results.

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 coverage is 60%, with query, start_date and end_date documented in the schema. The description adds meaning for query (it changes the default window to the current terms) and for page/limit (page returns the next batch). It does not clarify how start_date/end_date interact with the 7-day default or whether the window is inclusive, which is the main remaining ambiguity.

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 gives a specific verb and resource ('List the user's events') and narrows scope with '(ungraded calendar items)', which implicitly separates it from graded-item siblings like list_assignments and get_grades. It also flags a distinctive behavior, repeating events listed per occurrence. It stops short of naming a sibling to use instead, so it is clear but not fully differentiated.

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?

Usage is implied through the default windows: no arguments means the next 7 days, and supplying a query shifts the window to the current terms. There is no explicit statement of when to prefer this tool over list_assignments or the import/preview siblings, and no exclusions are given.

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