get_msg

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

No annotations are provided, so the description carries the full behavioral burden. It hints at return content (sender, time, raw segments) but says nothing about failure modes when the message_id is invalid, permission scope, or whether this only works for recent messages, which matters for a single-message fetch.

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?

The main sentence is efficient and front-loaded, but the trailing ':param message_id: 目标消息 ID' line is pure duplication of the schema and adds no value, slightly cluttering the definition.

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?

With no annotations and no output schema, the description does useful work by naming the returned fields. However, for a message-fetch tool it omits error handling and scope constraints, leaving the definition only minimally complete.

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% with a single, self-documented parameter. The description merely restates the schema ('目标消息 ID') without adding format, range, or example guidance, 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 (获取/get) and resource (单条消息/single message) and enumerates what it returns: sender, send time, raw message segments. This is clearly distinct from siblings like get_forward_msg or get_group_msg_history, though it doesn't explicitly name those alternatives.

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?

No when-to-use guidance and no alternatives referenced. It doesn't say how this differs from get_group_msg_history, get_recent_messages, or get_forward_msg, leaving the agent to infer selection from tool names alone.

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