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

Annotations already cover readOnly/idempotent/non-destructive, and the description adds substantial extra context: login requirement, the 3-day/1-day reminder windows, that opening does not confirm, the 4-hour SMS re-send for unconfirmed reminders, and that queries about time/location/transport are not confirmations.

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, then scope, then behavioral caveats in a compact set of sentences. It is dense but every sentence carries meaning; no 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 list tool with no output schema, the behavioral picture is largely complete. The remaining gap is the undocumented activityId parameter, which leaves a small ambiguity about filtering by a specific activity.

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 only 50%: pendingOnly is documented in the schema but activityId has no description anywhere, and the description itself never mentions either parameter. With half the parameters undocumented, the description fails to compensate for the coverage gap.

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 (列出/list) and resource (本人活动提醒) with a precise scope (前3天和前1天), so an agent knows exactly what set is returned. It does not name the sibling get_my_activity_reminder or acknowledge_activity_reminder explicitly, though the 'reading does not confirm' clause implicitly separates it from the acknowledge tool.

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?

Gives clear behavioral usage context: reading/queries are not confirmations, and if multiple reminders exist the agent should ask the user which one. It lacks an explicit when-to-use-this-vs-sibling statement, so it stops short of a 5.

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