Anthropic's Claude API: a practical guide
Anthropic's API lets you integrate Claude into your applications. Here are the essentials: getting started, models, tools and how billing works.
Getting started with the API
You create an API key from the Anthropic console, then call the Messages endpoint with an official SDK (Python, TypeScript) or over HTTP. You send messages and the model responds — text, structured JSON or tool calls.
Choosing the right model
The Claude family (Opus, Sonnet, Haiku) covers power/speed/cost trade-offs. Sonnet is the default, Opus for the most demanding work, Haiku for volume. See our models guide.
Tools, structured outputs and MCP
The API supports function calling (tools), structured outputs, and connects to data sources via the MCP protocol. That's the basis for building agents.
Pricing
The API is billed per usage, per token (input + output), with different rates per model. Amounts change: refer to the official page; our feed flags the changes.
Frequently asked questions
How do I get a Claude API key?
From Anthropic's developer console, after creating an account.
Which languages are supported?
Official SDKs exist for Python and TypeScript; the HTTP API works from any language.
How much does the Claude API cost?
Per-token billing, varying by model. Check the official pricing for current amounts.
What is MCP?
The Model Context Protocol, a standard to connect tools and data to models; see our dedicated page.
See also: the complete guide to Claude · Claude news in real time
Claude News is an independent publication, not affiliated with Anthropic.