claude-api Claude Code Skill

This skill is a reference guide for building applications on the Claude API and Anthropic SDKs. It is meant to be consulted whenever a task involves Claude/Anthropic model selection, pricing, limits, or any LLM-shaped work where the provider is not stated, and it explicitly steps aside when another provider such as OpenAI or Gemini is already in use. It documents current model identifiers and pricing, streaming, tool use, prompt caching, authentication, and agent-building patterns across several programming languages. It also defines named subcommands for tasks like migrating code to a newer Claude model, auditing prompts for outdated patterns, upgrading the SDK across major versions, reducing API cost, and building or improving evaluation sets. The skill does not itself connect to any external service beyond describing how to call the Claude API.