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

Annotations already declare readOnlyHint=true; the description reinforces this with '不标记已确认' and adds genuinely new behavior: a reminder becomes unconfirmable after the activity is cancelled, rescheduled, the signup is revoked, or permissions lapse. It also discloses the login requirement, which annotations do not cover. It does not describe error shapes or what fields the returned status contains.

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?

Two compact clauses: the operation and its key negative guarantee come first, then the stale-reminder caveat and the sibling hand-off. No redundant restatement of the tool name or schema.

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 one-parameter read tool with no output schema, the description covers what is returned (current info and confirmation status), the auth requirement, edge-state behavior, and where to go for adjacent data. Nothing needed to call 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% for the single reminderId parameter, and the schema already states it must be the caller's own reminder id, sourced from a chat reminder or the reminder list. The description's '本人一条' adds an ownership emphasis but no syntax or format meaning 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 and resource: read one of the caller's own activity reminders, returning its current info and confirmation status. It explicitly distinguishes itself by '不标记已确认' (side-effect free) and routes activity details to get_activity, so an agent can separate it from acknowledge_activity_reminder and get_activity without opening any 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?

Gives a clear when-to-use framing (inspect status without confirming) plus an explicit alternative for activity details and on-site guidance: get_activity. It also states the precondition 登录. The one gap is that the sibling that actually confirms a reminder (acknowledge_activity_reminder) is never named, so the agent must infer it from '不标记已确认'.

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