using-anthropic-platformlisted

# Anthropic Claude SDK - Quick Reference ## When to Use Load this skill when: - `anthropic` package in `requirements.txt` or `pyproject.toml` - `@anthropic-ai/sdk` in `package.json` dependencies - `ANTHROPIC_API_KEY` environment variable present - User mentions "Anthropic", "Claude", or Claude models **For detailed patterns**: See [REFERENCE.md](./REFERENCE.md) --- ## Table of Contents 1. [Claude Models](#claude-models-january-2026) 2. [Quick Start](#quick-start) 3. [Messages API Essentials](#messages-api-essentials) 4. [Streaming](#streaming) 5. [Tool Use (Function Calling)](#tool-use-function-calling) 6. [Extended Thinking](#extended-thinking) 7. [Vision](#vision) 8. [Prompt Caching](#prompt-caching) 9. [Error Handling](#error-handling) 10. [Platform Features](#platform-features) 11. [Further Reading](#further-reading) --- ## Claude Models (January 2026) | Model | Context | Max Output | Thinking | Best For | |-------|---------|------------|----------|----------| | `claude-opus-4-5-20251101` | 200K | 32K | Yes | Maximum intelligence | | `claude-sonnet-4-20250514` | 200K | 64K | Yes | Complex reasoning, coding | | `claude-3-5-sonnet-20241022` | 200K | 8K | No | Standard tasks | | `claude-3-5-haiku-20241022` | 200K | 8K | No | Simple chat, Q&A (cheapest) | ### Model Selection ``` Simple chat/Q&A -> claude-3-5-haiku (cheapest) Standard tasks -> claude-3-5-sonnet Complex reasoning/coding -> claude-sonnet-4 or claude-opus-4-5 Extended thinking nee