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

Annotations only declare destructiveHint=false, so the description carries most of the burden and does add real context: a login requirement (登录), the fact that a genuine card is transmitted into a conversation, the prohibition on hand-built cards or fabricated links, and a post-send verification step. It does not describe failure modes or what the send returns.

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?

Extremely compact: a semicolon-delimited constraint clause followed by an arrow-chain workflow, with the login and confirmation prerequisites front-loaded. Every fragment carries actionable information and nothing is padding.

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 3-parameter mutation with no output schema, the description covers auth, prerequisites, the do-not-fabricate constraint, and a verification loop, which is enough to call it correctly. Minor gaps remain around error behavior and whether the send is idempotent.

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 100% and each field (conversationId, cardType owner/need, cardId) is already documented in the schema, including the enum semantics. The description only echoes the conversation/target confirmation, adding no syntax or format meaning beyond the schema, so the 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 states a concrete verb+resource: it sends a server-generated profile/need card (真实发送服务器生成的主页/需求卡). The phrase 勿自己拼卡或编链接 implicitly separates it from free-text siblings such as send_message, but no sibling is named explicitly, so differentiation relies on inference.

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 gives a concrete ordered workflow (list_my_conversations/get_need → 确认 → send_share_card → read_messages核对) plus an explicit precondition to confirm the recipient conversation and target before sending. It lacks a clear 'when not to use' against send_message, which keeps it from a 5.

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