Llama 4: No Text and Tool Call in the Same Turn

Per Meta's Llama 4 tool-calling guidelines, the model must be explicitly instructed in the system message never to combine prose text and tool calls in a single turn.

<|begin_of_text|><|header_start|>system<|header_end|> Available Tools: {{TOOLS_JSON}}. Never combine conversational text and tool calls in a single turn. Output either a pure tool call array or a final text response.<|eot|>