3.0 KiB

Raw Blame History

API Key Setup Guide

Every lab needs at least one LLM API key. If you don't have one, the mock LLM handles everything offline.

Quick Start: Use the Mock LLM (No Key Needed)

All labs include automatic mock LLM fallback. Run without any setup:

python labs/L1-first-agent/solution.py test.txt "Summarize this file"

The mock client returns realistic responses. Your code runs identically with real or mock LLM.

Provider Keys

Anthropic (Claude) — Recommended

Best for: All course labs. Claude Sonnet is the default model used throughout.
Cost: Free credits available on signup. Labs cost ~$0.01-0.05 each with Sonnet.
Get key: console.anthropic.com
Set it:

# Windows PowerShell
$env:ANTHROPIC_API_KEY="sk-ant-..."

# Mac/Linux
export ANTHROPIC_API_KEY="sk-ant-..."

OpenAI (GPT)

Best for: Labs using the OpenAI SDK.
Cost: Free credits on signup. GPT-4o costs ~$0.02-0.10 per lab.
Get key: platform.openai.com/api-keys
Set it:

export OPENAI_API_KEY="sk-..."

Google Gemini

Best for: Cost-sensitive experimentation. Gemini Flash is $0.15/M tokens.
Cost: Free tier available (60 requests/minute).
Get key: aistudio.google.com/apikey
Set it:

export GEMINI_API_KEY="..."

OpenRouter (Multi-Provider)

Best for: Accessing multiple models from one key.
Cost: Pay-as-you-go. Free tier available for some models.
Get key: openrouter.ai/keys
Set it:

export OPENROUTER_API_KEY="sk-or-..."

Which Key Should You Get?

If you...	Get
Want the simplest setup	None (use mock LLM)
Want to follow the course exactly	Anthropic (Claude Sonnet)
Already have OpenAI access	OpenAI (GPT-4o or o3-mini)
Want the cheapest option	Gemini (Flash is $0.15/M)
Want to try different models	OpenRouter (one key for everything)

Testing Your Key

# Anthropic
python -c "from anthropic import Anthropic; c=Anthropic(); print(c.messages.create(model='claude-sonnet-4', max_tokens=50, messages=[{'role':'user','content':'hi'}]).content)"

# OpenAI
python -c "from openai import OpenAI; c=OpenAI(); print(c.chat.completions.create(model='gpt-4o', messages=[{'role':'user','content':'hi'}]).choices[0].message.content)"

# Mock (no key needed)
python -c "from mock_llm import MockAnthropic; c=MockAnthropic(); print(c.messages.create(messages=[{'role':'user','content':'hi'}]).content[0].text)"

Free Tier Limits

Provider	Free Credits	Rate Limit
Anthropic	$5-10 signup credit	Varies by model
OpenAI	$5-18 signup credit	Varies by tier
Gemini	Free tier (60 req/min)	60 requests/minute
OpenRouter	Varies by model	Varies

The course uses ~$0.50-2.00 in API costs total with Anthropic, or $0 with the mock LLM.

3.0 KiB Raw Blame History