wechat_send_message

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

No annotations are supplied, so the description carries the full behavioral burden, yet it says nothing about the fact that this sends an irreversible real message to a real contact, what happens if the name matches multiple contacts, whether a WeChat login is required, or rate limiting. Only the schema's incidental note about >2000-character messages becoming txt files adds behavior.

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?

A single front-loaded sentence with zero filler; the scope qualifiers appear before any call to action.

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?

An output schema exists so return values need no explanation and parameters are fully documented, but for a side-effecting outbound-message tool with no annotations the description omits preconditions, ambiguity handling for name matching, and failure behavior — gaps an agent needs before calling it.

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% — to_user, message, delay and search_pages all carry their own descriptions including the 2000-character behavior and the meaning of search_pages=0. The description adds no parameter semantics beyond that, so 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 (发送一条消息) plus scope qualifiers (单个好友或群聊、一条) that directly contrast with siblings like wechat_send_multiple_messages and wechat_send_to_multiple_friends. An agent can pick this tool over those siblings without opening any schema.

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 words 单个 and 一条 imply the single-recipient, single-message case and thus hint that bulk sends belong to the sibling tools, but no alternative is named and no prerequisites (e.g. must be logged in) are given. Usage is implied rather than stated.

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