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Tool Calling & Selection
The process where an LLM selects an available tool and outputs a structured request (JSON) to run external code instead of plain text.
Why it exists
LLMs cannot perform math, search live web data, or execute code natively. Tool calling lets models delegate actions to APIs.
How it works
System passes tool schemas -> LLM evaluates prompt -> Model outputs JSON string { 'name': 'search', 'args': {'query': 'X'} } -> App executes function.