Structured Output and Tool Use with Local LLMs (October 2026)
JSON mode, GBNF grammar-constrained decoding, and OpenAI-style tool calling across Ollama, llama-server, LM Studio, and vLLM.
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JSON mode, GBNF grammar-constrained decoding, and OpenAI-style tool calling across Ollama, llama-server, LM Studio, and vLLM.
Anthropic's newest Claude models hallucinate extra fields when calling third-party tools like Pi because their post-training now mimics Claude Code's schema.
Which local models can actually use tools, call functions, and run multi-step workflows? Function-calling and TAU-bench picks from 8GB to 32GB VRAM.