Checklist

• 1. If the issue you raised is not a feature but a question, please raise a discussion at https://github.com/sgl-project/sglang/discussions/new/choose Otherwise, it will be closed.
• 2. Please use English, otherwise it will be closed.

Motivation

Function calling is crucial for building agentic systems, allowing agents to interact with external tools, APIs, and other agents to handle complex tasks. I noticed that this feature was included in the Q3 roadmap with an associated PR, but it appears to have stalled and was removed from the Q4 roadmap. Given the growing demand for agentic systems, I hope to see this feature prioritized and implemented in SGLang.

Related resources

Maybe vLLM https://docs.vllm.ai/en/latest/usage/tool_calling.html could provides some insight into the implementation.