Claude 3 Quickstart Chat API

 import logging
import os
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
from typing import Optional
import anthropic 

logger = logging.getLogger(__name__)

app = FastAPI()

client = anthropic.Anthropic(

class ChatRequest(BaseModel):
    system_prompt: Optional[str] = "You are a helpful assistant. Respond to the following question/statement."
    user_prompt: str
    model: Optional[str] = "claude-3-opus-20240229"
    temperature: Optional[float] = 1.0
    max_tokens: Optional[int] = 1000"/ask-claude/")

About this template

A Chat API that allows you to immediately integrate any application you're building with the largest anthropic model (Claude Opus) with only your API key. Once you run the app, you can use this app's "/ask-claude" endpoint to send a request to Claude 3 from any application you build.

Introduction to the Claude 3 Quickstart Chat API Template

Welcome to the Claude 3 Quickstart Chat API template guide. This template is designed to help you integrate a powerful AI chatbot, powered by the Claude 3 model, into your applications with ease. Whether you're building a customer service bot, an interactive tool for your website, or any other application that could benefit from AI-powered conversation, this template is a great starting point.

Clicking Start with this Template

To begin using this template, simply click on the "Start with this Template" button in the Lazy Builder interface. This will pre-populate the code in the Lazy Builder, so you won't need to copy or paste any code manually.

Initial Setup

Before you can start using the chat API, you'll need to set up an environment secret for your API key. Here's how to do it:

  • Go to the Environment Secrets tab within the Lazy Builder.
  • Create a new secret with the key "ANTHROPIC_API_KEY".
  • For the value, you'll need to obtain an API key from Anthropic. Visit the Anthropic website, sign up for an account, and generate an API key from your dashboard.
  • Once you have your API key, enter it as the value for the "ANTHROPIC_API_KEY" secret.

Test: Pressing the Test Button

With your API key set up as an environment secret, you're ready to test the app. Press the "Test" button in the Lazy Builder. This will deploy your app and launch the Lazy CLI. You will not need to provide any user input at this stage.

Using the App

After pressing the "Test" button, Lazy will print a dedicated server link that you can use to interact with your new AI Chat API. Additionally, since this template uses FastAPI, you will also be provided with a link to the FastAPI documentation, which includes interactive API documentation.

To communicate with the AI, send a POST request to the "/ask-claude/" endpoint with a JSON payload that includes the user prompt and any optional parameters you wish to set. Here's a sample request:

POST /ask-claude/
Content-Type: application/json

  "user_prompt": "What is the weather like today?",
  "temperature": 0.7

And here's what a sample response might look like:

  "message": "The weather today is partly cloudy with a high of 22 degrees Celsius."

Integrating the App

If you're looking to integrate this chat API into an external service or frontend, you'll need to use the server link provided by Lazy. For example, if you're building a web application, you can make AJAX requests to the provided server link to send and receive messages from the AI.

Remember, this template is just the beginning. You can customize the code to fit the specific needs of your application, such as adding authentication, integrating with other services, or enhancing the AI's capabilities with additional logic.

With this guide and the Claude 3 Quickstart Chat API template, you're well on your way to building an engaging and intelligent chat experience for your users. Happy building!

Last published
July 20, 2024

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Claude 3 Quickstart Chat API