Setting Up Your Anthropic API Key & Local Environment

Setup in 10 minutes

1. Create an API key

1. Go to https://console.anthropic.com.
2. Create an organisation if you do not have one.
3. Keys → Create Key. Copy it once — you will not see it again.
4. Save to .env (never commit): ANTHROPIC_API_KEY=sk-ant-....

2. Install the SDK

Python:

pip install -U anthropic

Node.js:

npm install @anthropic-ai/sdk

PHP (used throughout this course for Laravel examples):

composer require openai-php/laravel # via adapter, or call HTTP directly

3. Verify the key works

from anthropic import Anthropic

client = Anthropic()
msg = client.messages.create(
    model="claude-opus-4-7",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Ping"}],
)
print(msg.content[0].text)

4. Billing setup

Start with the $5 free tier to validate your key. Upgrade to Tier 1 (~$100 prepaid) before building anything serious — rate limits scale with tier.

5. Observability from day one

Log every request/response with timestamp, model, input tokens, output tokens, cost. A simple JSONL log saves you hours when debugging.

That is all the setup. Next lesson we ship a real request.