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

Annotations already declare readOnly=false, idempotent=false and openWorld=true. The description adds value beyond them: login/auth is required, the send is real and irreversible-ish ('真实发送'), and the agent must verify the conversation and target beforehand and must not fabricate card links.

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?

Dense, front-loaded with the login requirement and the send constraint in bracketed chunks, with no filler sentences. The 【】notation is terse and the chain segment slightly overlaps the usage guidance.

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-required-param mutation with no output schema, the description supplies the auth precondition, the confirmation step, the sourcing chain and a post-send verification step via read_messages. An agent has enough to call it correctly without return-value docs.

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%, so conversationId/cardType/cardId and the owner-vs-need id distinction are already documented. The description only implies where ids come from via the chain (list_my_conversations, get_need), which is marginal added value; 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?

States a specific verb+resource (真实发送...主页/需求卡) and sharply delimits scope by forbidding self-constructed cards or fabricated links. It is clearly distinct from a plain send_message, though it never names that sibling explicitly as the alternative.

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?

Gives a real prerequisite (需要登录) and an explicit operating order: confirm the receiving conversation and share target first, then the combo chain list_my_conversations/get_need → send_share_card → read_messages to verify. What is missing is an explicit 'use X instead when...' exclusion versus send_message.

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