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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds genuinely non-redundant behavior: 【需要登录】 (login required), that results include cancelled history, and that unpublishing does not change status so 'displaying' must be used to separate. These are meaningful operational facts not derivable from annotations.

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?

Uses bracketed sections (【需要登录】, 【组合链】) to front-load the login requirement and the id-combo chain, and every clause carries information. It is dense to the point of terseness but avoids 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 read-only list tool with rich annotations, 100% schema coverage, and no output schema, the description covers auth, result scope, the displaying-vs-status trap, and follow-up tools. 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?

Schema coverage is 100%, so baseline is 3, but the description adds real semantics beyond the schema: it clarifies that 'displaying' (not status=OPEN) is the true on-shelf visibility signal, and that displaying=true should be passed only for on-shelf items. This directly disambiguates two easily-confused parameters.

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 and resource ('列本人需求' – list my own needs) and immediately scopes it with '含取消历史' (including cancelled history). The '本人' qualifier cleanly separates it from sibling feed/search tools like list_needs_feed and search_needs without needing the schemas.

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?

Routes the agent to explicit alternatives: get_conversation_needs for claim/completion state and get_need_recommendations for recommendations. It also warns not to infer on-shelf visibility from OPEN. It lacks a direct when-to-use comparison against list_needs_feed/search_needs, so it falls just short of a full 5.

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