Getting Started
Getting started with the Claude API — issuing keys, billing, your first call, and error handling with retries.
7 articles
How to Get a Claude Code API Key: Console Setup Guide
A step-by-step guide to generating an API key in the Claude Console and connecting it to Claude Code with an environment variable.
Claude API Payment Failing? Fix Credit Balance & Billing Errors (2026)
Fix Claude API payment and credit errors by error code: 400 balance-too-low, 402 billing, 429 rate limit, plus how to top up and prevent recurrence — based on official docs.
Is the Claude API Free? Free Credits, Free Alternatives & Pricing (2026)
The Claude API has no permanent free tier. Here are 4 ways to use Claude for free — starter credits, the claude.ai Free plan, and credit programs — plus actual pay-as-you-go pricing, based on official sources.
Claude API Vision — How to Send Images and PDFs as Input
Learn how to send images to Claude via the API using three methods: Base64 encoding, URL reference, and the Files API. Step-by-step examples included for beginners.
Claude API Error Handling, Retries & Rate Limits: Complete Guide
Classify Claude API HTTP error codes (400–529) as retryable or not, and learn retry-after, exponential backoff with jitter for 429/5xx, SDK typed exceptions, and request size limits — all based on official docs.
Claude API Keys: Getting a Key, Pricing & Usage (2026)
You need an API key to call Claude from code. This guide covers how to get a key, current model pricing including Sonnet 5, and how to keep your key secure.
Getting Started with the Claude API: Your First Call (Developer Intro)
How a developer makes their first Claude API call: getting a key, x-api-key auth, the first Messages endpoint call (curl), model strings, and how billing works.