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Claude Certified Developer — Foundations

Anthropic · Topic 2 of 5

Tool Use and Function Calling

Giving Claude tools: defining tools with JSON schemas, the tool_choice modes (auto / any / forced), the request→tool_use→execute→tool_result loop, parallel tool calls in one turn, and returning results and errors (the isError flag).

5 lessons213 questions
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What this topic covers

  1. 01Defining Tools with JSON Schemas300m
  2. 02tool_choice: auto, any, tool, and none300m
  3. 03The Tool-use Loop360m
  4. 04Parallel Tool Calls300m
  5. 05Returning Results and Errors (isError)300m

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