Together AI expands fine-tuning service with tool calling, reasoning, and vision support

This post introduces native support for tool call, reasoning, and vision-language model (VLM) fine-tuning within the Together Fine-Tuning platform. It details the engineering behind ensuring reliability for these capabilities, including schema validation for tool calls, structured reasoning trace handling, and inline base64 encoded image support for VLM training. The post also highlights infrastructure upgrades for large model fine-tuning (up to 1T parameters) with up to 6x higher throughput achieved through optimizations like SonicMoE kernels and custom CUDA kernels for loss computation, and the elimination of GPU-to-CPU synchronization points. New features include pre-training cost estimations and dynamic ETA tracking.