Build with Claude Messages API using structured outputs (v0.69.0+, Nov 2025) for guaranteed JSON schema validation. Covers prompt caching (90% savings), streaming SSE, tool use, model deprecations (3.5/3.7 retired Oct 2025). Use when: building chatbots/agents with validated JSON responses, or troubleshooting rate_limit_error, structured output validation, prompt caching not activating, streaming SSE parsing. apiKey: process.env.ANTHROPIC_API_KEY, model: claude-sonnet-4-5-20250929, max_tokens: 10
/plugin marketplace add jezweb/claude-skills/plugin install claude-api@jezweb/claude-skills