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

The description is consistent with readOnlyHint=true and adds substantial behavior beyond it: an auth prerequisite, the 10-activity cap, merge semantics via missingCombined, default scoping, formUnknown requiring the externalUrl to be opened, requiresAppActivation being a placeholder that only the user's App can confirm, and the warning that zero gaps does not mean the signup can be submitted directly. It also flags a privacy constraint (includeMyAnswers contains the user's own contact details, must not be forwarded) and that sensitive answers must be re-entered on site.

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?

Length is reasonable, but the text is a semicolon-chained wall of telegraphic clauses with undefined internal identifiers (missingCombined, formUnknown, requiresAppActivation) appearing before any explanation. The most important information — what the tool returns — is buried behind the login note rather than front-loaded.

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 read-only computation tool with full schema coverage and no output schema, the description covers the prerequisites, default scoping, edge cases (zero gaps ≠ submittable, app-only confirmations, external forms), privacy handling, and the natural follow-up siblings. It stops short of describing the response shape or pagination, and the unexplained identifiers leave some ambiguity about what fields come back.

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%, so the baseline is 3, but the description adds real meaning: it clarifies the default-vs-explicit-slugs scoping tradeoff (unregistered activities by default, registered ones only when slugs are passed) and warns that includeMyAnswers output carries the user's personal contact information and should not be shared with third parties. The q/kind/limit parameters get no added explanation, which is acceptable given the schema documents them.

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 tool's actual job — batch-computing which signup questions are still missing across up to 10 activities, merged by missingCombined — is only implied by the clause '≤10场缺项按missingCombined合并，问一轮'. The sentence opens with an auth note ('登录') rather than a clean verb+resource statement, and never plainly says 'returns the missing items per activity'. It does distinguish itself from get_signup_activity ('看题'), but the core purpose has to be reconstructed from fragments.

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 routing is provided: get_signup_activity to see questions, update_my_signup_profile to store reusable answers then submit_signup, prepare_signup_file_upload for ordinary attachments, App for sensitive ones. Default scope is stated ('默认取未报场次，显式slugs才含已报'). No explicit when-not-to-use case is given, but conditions for choosing alternatives are clear.

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