提示使服务器能够定义可复用的提示模板和工作流程,客户端可以轻松将其呈现给用户和大型语言模型(LLM)。它们提供了一种标准化和共享常见 LLM 交互的强大方式。
提示设计为用户控制,意味着它们从服务器暴露给客户端,目的是让用户能够明确选择使用它们。
MCP 中的提示是预定义的模板,可以:
每个提示的定义包括:
{
name: string; // 提示的唯一标识符
description?: string; // 可读的描述
arguments?: [ // 可选参数列表
{
name: string; // 参数标识符
description?: string; // 参数描述
required?: boolean; // 参数是否为必填
}
]
}
客户端可以通过 prompts/list
端点发现可用提示:
// 请求
{
method: "prompts/list"
}
// 响应
{
prompts: [
{
name: "analyze-code",
description: "分析代码以寻找潜在改进",
arguments: [
{
name: "language",
description: "编程语言",
required: true
}
]
}
]
}
要使用提示,客户端发起 prompts/get
请求:
// 请求
{
method: "prompts/get",
params: {
name: "analyze-code",
arguments: {
language: "python"
}
}
}
// 响应
{
description: "分析 Python 代码以寻找潜在改进",
messages: [
{
role: "user",
content: {
type: "text",
text: "请分析以下 Python 代码以寻找潜在改进:\n\n```python\ndef calculate_sum(numbers):\n total = 0\n for num in numbers:\n total = total + num\n return total\n\nresult = calculate_sum([1, 2, 3, 4, 5])\nprint(result)\n```"
}
}
]
}
提示可以是动态的,包括:
{
"name": "analyze-project",
"description": "分析项目日志和代码",
"arguments": [
{
"name": "timeframe",
"description": "分析日志的时间段",
"required": true
},
{
"name": "fileUri",
"description": "要审查的代码文件的 URI",
"required": true
}
]
}
处理 prompts/get
请求时:
{
"messages": [
{
"role": "user",
"content": {
"type": "text",
"text": "分析这些系统日志和代码文件是否存在问题:"
}
},
{
"role": "user",
"content": {
"type": "resource",
"resource": {
"uri": "logs://recent?timeframe=1h",
"text": "[2024-03-14 15:32:11] ERROR: Connection timeout in network.py:127\n[2024-03-14 15:32:15] WARN: Retrying connection (attempt 2/3)\n[2024-03-14 15:32:20] ERROR: Max retries exceeded",
"mimeType": "text/plain"
}
}
},
{
"role": "user",
"content": {
"type": "resource",
"resource": {
"uri": "file:///path/to/code.py",
"text": "def connect_to_service(timeout=30):\n retries = 3\n for attempt in range(retries):\n try:\n return establish_connection(timeout)\n except TimeoutError:\n if attempt == retries - 1:\n raise\n time.sleep(5)\n\ndef establish_connection(timeout):\n # 连接实现\n pass",
"mimeType": "text/x-python"
}
}
}
]
}
const debugWorkflow = {
name: "debug-error",
async getMessages(error: string) {
return [
{
role: "user",
content: {
type: "text",
text: `我遇到了一个错误:${error}`
}
},
{
role: "assistant",
content: {
type: "text",
text: "我会帮助分析这个错误。你目前尝试了哪些方法?"
}
},
{
role: "user",
content: {
type: "text",
text: "我尝试过重启服务,但错误仍然存在。"
}
}
];
}
};
以下是在 MCP 服务器中实现提示的完整示例:
import { Server } from "@modelcontextprotocol/sdk/server";
import {
ListPromptsRequestSchema,
GetPromptRequestSchema
} from "@modelcontextprotocol/sdk/types";
const PROMPTS = {
"git-commit": {
name: "git-commit",
description: "生成 Git 提交消息",
arguments: [
{
name: "changes",
description: "Git 差异或更改描述",
required: true
}
]
},
"explain-code": {
name: "explain-code",
description: "解释代码的工作原理",
arguments: [
{
name: "code",
description: "要解释的代码",
required: true
},
{
name: "language",
description: "编程语言",
required: false
}
]
}
};
const server = new Server({
name: "example-prompts-server",
version: "1.0.0"
}, {
capabilities: {
prompts: {}
}
});
// 列出可用提示
server.setRequestHandler(ListPromptsRequestSchema, async () => {
return {
prompts: Object.values(PROMPTS)
};
});
// 获取特定提示
server.setRequestHandler(GetPromptRequestSchema, async (request) => {
const prompt = PROMPTS[request.params.name];
if (!prompt) {
throw new Error(`未找到提示:${request.params.name}`);
}
if (request.params.name === "git-commit") {
return {
messages: [
{
role: "user",
content: {
type: "text",
text: `为以下更改生成一个简洁但描述性的提交消息:\n\n${request.params.arguments?.changes}`
}
}
]
};
}
if (request.params.name === "explain-code") {
const language = request.params.arguments?.language || "未知";
return {
messages: [
{
role: "user",
content: {
type: "text",
text: `解释以下 ${language} 代码的工作原理:\n\n${request.params.arguments?.code}`
}
}
]
};
}
throw new Error("未找到提示实现");
});
实现提示时:
提示可以在客户端 UI 中呈现为:
服务器可以通知客户端有关提示更改的信息:
prompts.listChanged
notifications/prompts/list_changed
实现提示时: