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

Beyond readOnlyHint=true the description adds real behavioral facts: login is required, results are capped at 50 with newest-first ordering, answers are trimmed to key lists unless includeAnswers is set, and the status vocabulary is decoded (DELIVERY_FAILED means an external proxy submission failed and must be resubmitted manually; PENDING is unprocessed, not a rejection; SHORTLISTED means shortlisted). Crucially it separates delivery status from admission outcome, which prevents a serious misreading of results.

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 record cap and ordering before any status semantics, and every clause carries information. It is telegraphic to the point of opacity in places, notably '（覆盖上版）', which is not self-explanatory and costs the reader a beat.

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-only lister with no output schema, the description covers return contents, ordering, the 50-record ceiling, auth requirement, field trimming default, and the meaning of each status value. Nothing an agent needs in order to call it and interpret the result is absent.

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 parameter already documents its default and the key-list-only behavior, so the description largely restates it ('默认仅答案keys，要内容显式includeAnswers'). The restatement usefully emphasizes that full content costs payload, but it adds no syntax or format detail beyond the schema, so 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?

The description enumerates exactly what the tool returns for the caller's own signups (delivery status, host reviewStatus, messages) and caps scope at 50 records, newest first, which lets an agent separate it from the organizer-side siblings. It never states the listing verb outright; the reader infers 'list my signups' from the title plus the field inventory, so it falls just short of fully self-contained purpose.

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?

It explicitly routes follow-up work elsewhere: supplementing materials goes get_signup_activity -> submit_signup, and multi-record gaps go get_signup_gaps. That is clear conditional guidance. What is missing is disambiguation against the other listing siblings in this cluster (list_signup_feed, list_signup_submissions, list_my_activity_history), so an agent could still pick the wrong lister.

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