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Claude Certified Developer — Foundations

Anthropic · Topic 1 of 5

The Messages API

The core request/response contract: request anatomy (model, max_tokens, system, messages), statelessness and sending full history each turn, multi-turn conversations, assistant prefills, stop_reason semantics, and streaming responses.

5 lessons298 questions
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What this topic covers

  1. 01Request Anatomy: model, max_tokens, system, messages300m
  2. 02Statelessness: Sending Full History Each Turn240m
  3. 03System Prompts and Assistant Prefills300m
  4. 04stop_reason: end_turn, tool_use, max_tokens300m
  5. 05Streaming Responses (SSE)300m

Other topics in Claude Certified Developer — Foundations

Tool Use and Function Calling5 lessonsStructured Output and Prompt Techniques5 lessonsPerformance, Cost, and Reliability5 lessonsIntegrating MCP and the SDKs5 lessons