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

Annotations only supply idempotentHint and destructiveHint, and the description corroborates idempotency by stating that re-calling does not invalidate already-sent links. Beyond that it discloses a security constraint (the link is a secret, never post it on public pages) and an eligibility constraint (public activities only). This is the kind of context annotations cannot carry.

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-loaded with actor and action, then prerequisites, then constraints. Every clause carries information, though the telegraphic style ('剩不足一天换新', '给exits') is dense enough to risk misparsing on first read.

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?

No output schema exists, and the description does not state the response shape or field name for the returned URL, which is the one meaningful gap. Prerequisites, reuse logic, idempotency, secrecy and eligibility are all covered for what is a single-parameter tool.

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?

There is one parameter at 100% schema coverage, so the baseline is 3; the description earns a bump because '仅公开活动可建' constrains which activityRef values are valid, which the schema does not express. It still adds no format detail beyond the schema's slug-or-id note.

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 states a specific verb+resource: creating a guest 'self-recommendation' (自荐) link that the end user forwards to group chats. The '供用户本人转群' clause implicitly separates it from the collection/invite-link siblings (create_guest_collection_link, create_guest_invite_link), but it never names those alternatives explicitly, so an agent must infer the distinction.

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?

Explicit sequencing: call get_activity_invites first and reuse an existing openInvite URL. It further states the renewal threshold (renew when under one day remains) and the exclusion case (org-internal or targeted activities are rejected with exits). Both when-to-use and when-not-to-use are covered.

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