如何在调用工具时使用少样本提示
前提条件
本指南假定您熟悉以下概念：
在更复杂的工具使用场景中，在提示中添加少量示例是非常有帮助的。我们可以通过在提示中添加包含
ToolCalls 的 AIMessages 以及相应的 ToolMessages 来实现这一点。
首先定义一个模型和一个计算器工具：
import { tool } from "@langchain/core/tools";
import { z } from "zod";
import { ChatOpenAI } from "@langchain/openai";
const llm = new ChatOpenAI({ model: "gpt-4o", temperature: 0 });
/**
* Note that the descriptions here are crucial, as they will be passed along
* to the model along with the class name.
*/
const calculatorSchema = z.object({
operation: z
.enum(["add", "subtract", "multiply", "divide"])
.describe("The type of operation to execute."),
number1: z.number().describe("The first number to operate on."),
number2: z.number().describe("The second number to operate on."),
});
const calculatorTool = tool(
async ({ operation, number1, number2 }) => {
// Functions must return strings
if (operation === "add") {
return `${number1 + number2}`;
} else if (operation === "subtract") {
return `${number1 - number2}`;
} else if (operation === "multiply") {
return `${number1 * number2}`;
} else if (operation === "divide") {
return `${number1 / number2}`;
} else {
throw new Error("Invalid operation.");
}
},
{
name: "calculator",
description: "Can perform mathematical operations.",
schema: calculatorSchema,
}
);
const llmWithTools = llm.bindTools([calculatorTool]);
我们的计算器可以处理常见的加法、减法、乘法和除法。但是，如果我们询问一个新的数学运算符
🦜 会出现什么情况呢？
让我们看看如果直接使用它会出现什么情况：
const res = await llmWithTools.invoke("What is 3 🦜 12");
console.log(res.content);
console.log(res.tool_calls);
[
{
name: 'calculator',
args: { operation: 'multiply', number1: 3, number2: 12 },
type: 'tool_call',
id: 'call_I0oQGmdESpIgcf91ej30p9aR'
}
]
它不太清楚如何将 🦜 解释为一个运算符，默认情况下会将其视为
multiply（乘法）。现在，我们尝试以构造消息的形式给它一些示例，引导它将
🦜 理解为 divide（除法）：
import { HumanMessage, AIMessage, ToolMessage } from "@langchain/core/messages";
const res = await llmWithTools.invoke([
new HumanMessage("What is 333382 🦜 1932?"),
new AIMessage({
content:
"The 🦜 operator is shorthand for division, so we call the divide tool.",
tool_calls: [
{
id: "12345",
name: "calculator",
args: {
number1: 333382,
number2: 1932,
operation: "divide",
},
},
],
}),
new ToolMessage({
tool_call_id: "12345",
content: "The answer is 172.558.",
}),
new AIMessage("The answer is 172.558."),
new HumanMessage("What is 6 🦜 2?"),
new AIMessage({
content:
"The 🦜 operator is shorthand for division, so we call the divide tool.",
tool_calls: [
{
id: "54321",
name: "calculator",
args: {
number1: 6,
number2: 2,
operation: "divide",
},
},
],
}),
new ToolMessage({
tool_call_id: "54321",
content: "The answer is 3.",
}),
new AIMessage("The answer is 3."),
new HumanMessage("What is 3 🦜 12?"),
]);
console.log(res.tool_calls);
[
{
name: 'calculator',
args: { number1: 3, number2: 12, operation: 'divide' },
type: 'tool_call',
id: 'call_O6M4yDaA6s8oDqs2Zfl7TZAp'
}
]
而且我们可以看到它现在以正确的方式将 🦜 等同于 divide 操作！