Claude API Reference

claudeanthropicapisdkllm

Summary

Authoritative reference for the Claude API and Anthropic SDKs — model IDs, pricing, parameters, streaming, tool use, MCP, agents, prompt caching, and token counting.

Features

Current model IDs and pricing
Request parameters and streaming
Tool use and MCP integration
Prompt caching and token counting
Model-migration guidance

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Skill Content

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# Claude API Reference

Use this skill whenever you are writing code against the Claude API or Anthropic SDK, or answering questions about models, pricing, limits, or caching.

## Covers
- Model IDs and pricing for the current Claude lineup
- Messages API parameters, streaming, and stop reasons
- Tool use, the Tool Runner loop, and MCP
- Managed agents, prompt caching, and token counting
- Migrating between model versions

## Why use it
LLM details change often; answering from memory produces stale model names and wrong prices. This skill grounds answers in current reference material.

Description

A reference skill for building on the Claude API and the Anthropic SDKs. It covers current model IDs and pricing, request parameters, streaming, tool use, the Model Context Protocol, agent patterns, prompt caching, token counting, and model-migration guidance — so integrations use accurate, up-to-date details instead of guesses from memory.