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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds real value beyond that: a login requirement and the staleness rule (cancelled, rescheduled, revoked-signup, or expired-permission reminders cannot be confirmed), which an agent could not infer from annotations.

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?

Front-loads the login requirement and the core read semantics, then appends the staleness caveat and the alternative-tool pointer. Dense and mostly waste-free, though it packs several distinct ideas into one long sentence.

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 single-parameter tool with no output schema and full schema coverage, the description covers the gaps that matter: auth requirement, non-mutating behavior, staleness constraints, and the correct sibling to use for activity details. Nothing needed to invoke it correctly is 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 coverage is 100% and the single reminderId parameter is fully documented in the schema (including its source in chat reminders or the reminder list). The description adds no syntax or format detail beyond that, so the baseline 3 applies.

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?

States a specific verb (读取/read), a precise resource (一条活动提醒/one activity reminder), and scope (本人/own). It explicitly distinguishes itself from the confirming action ('不标记已确认'), so an agent can separate it from acknowledge_activity_reminder without opening either schema.

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?

Names an alternative and the condition that selects it ('活动详情和到场指引用 get_activity') and clarifies that this read does not confirm. It does not, however, explicitly contrast with the sibling list_my_activity_reminders, so the routing picture is clear but not exhaustive.

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