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

Annotations only say readOnlyHint=false, but the description adds substantial behavioral context: login requirement, one-time link with 10-minute expiry, permission re-check on open, 20,000-row limit, and a warning that CSV body must never enter model context. This goes far beyond what annotations provide.

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?

The description is front-loaded with the trigger condition and core behavior, then organized into a clear numbered list addressing workflow, caveats, and safety warnings. Although lengthy, every sentence carries essential security or usage information, making the length justified.

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?

Despite having no output schema, the description fully explains what the tool returns (a signed link, not CSV), how the user consumes it, what to do on expiry, and important safety constraints. Combined with the schema and annotations, nothing critical is missing for correct invocation.

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?

The schema covers the only parameter (slug) with 100% coverage, so the baseline is 3. The description does not add additional meaning to slug beyond what the schema already states, but given full schema coverage, no compensation is needed.

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 and resource: issuing a one-time signed download link for the signup list export, and explicitly contrasts it with returning CSV content. It clearly differentiates this from sibling tools like list_signup_submissions and bulk_review_signup_submissions.

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?

The description gives explicit trigger conditions ('用户说把报名表给我 / 导出名单 / 我要下载 Excel'), a recommended sequence with list_signup_submissions first, and a clear alternative (bulk_review_signup_submissions) when per-person handling is needed instead of a full export. It also instructs to re-call the tool if the link expires.

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