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

Adds substantial context beyond annotations: it discloses the management-permission requirement, the two-step preview→confirm workflow (same params + previewHash, preview=false, re-confirm on change), and re-verification of identity, phone and audience at fill time. Annotations only cover the safety profile, so this is real added behavioral information.

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 the permission requirement in brackets, then scope, then the workflow. Dense but every clause carries meaning; slight cost from packing multiple rules into run-on clauses, but 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 mutating, open-world tool with no output schema, the description covers auth, targeting rules, and the preview/confirm lifecycle well. Return values are not described, but no output schema exists so that is not required; remaining gap is minor.

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 0%, so the description carries the burden and mostly does: it explains preview's default, the previewHash confirmation mechanic, and that targetUserId is mandatory for private activities. activityRef itself is only implied as the subject activity, so one of four params is left slightly under-explained.

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+resource: prepare general/targeted filling links, and immediately delimits scope with '不代发、不扩大受众' (does not send, does not expand audience). This lets an agent separate it from send_guest_invite_now and similar send tools, though it does not name the closest siblings (create_guest_invite_link / create_guest_open_link) explicitly.

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 concrete when-to-use conditions: private activities require targetUserId plus existing audience eligibility, targeted links are handed only to the person, and the default is preview with confirmation via previewHash. No explicit exclusion of a named alternative, but the '不代发' clause implies when another tool should be used instead.

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