sglang

Serve structured LLM generations with RadixAttention prefix caching.

Updated Aug 23, 2026
One-click install
npx skills add https://github.com/box755/simlens-research --skill sglang-box755
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: sglang
Source: https://github.com/box755/simlens-research/tree/main/skill-packs/AI-Research-SKILLs/12-inference-serving/sglang
Command: npx skills add https://github.com/box755/simlens-research --skill sglang-box755

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires sglang, torch, transformers, and includes references (resource) components.

What problem does it solve?

SGLang solves slow and inconsistent LLM serving when you need structured outputs (like JSON/regex/grammar) and repeated prompt prefixes across many requests, by reusing cached computation through RadixAttention.

Core Features & Use Cases

  • Fast structured generation: Produce valid JSON via constrained decoding, including regex constraints and grammar-based generation.
  • RadixAttention prefix caching: Automatically caches and reuses shared prompt prefixes (e.g., system prompts, few-shot examples, tool definitions) to reduce repeated KV computation.
  • Production serving + agent workflows: Run an OpenAI-compatible inference server and support tool/function calling patterns for agentic applications where prompts are largely repeated but queries vary.
  • Use Case: Build an agent that repeatedly uses the same system prompt and tool schema while handling many user queries; RadixAttention reuses the shared prefix so each new request computes only the new suffix.

Quick Start

Use the sglang skill to launch a local OpenAI-compatible server and generate constrained JSON answers with RadixAttention enabled.

Frequently Asked Questions about sglang

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I speed up structured LLM generation when prompts share the same prefix?

Speed up structured LLM generation by using RadixAttention prefix caching to automatically cache and reuse shared prompt prefixes, reducing repeated KV computation for JSON or regex-constrained outputs.

What is the best way to serve regex and JSON schema constrained outputs for production inference?

Serve regex and JSON schema constrained outputs efficiently using an OpenAI-compatible SGLang server, leveraging constrained decoding parameters and RadixAttention for production inference.

Does RadixAttention work with tool calling and agent workflows?

RadixAttention works with tool calling agent workflows by reusing shared prompt prefixes like system prompts and tool definitions, computing only the new suffix for each varying user query.

How do I set up my environment for prefix caching and structured generation?

Set up prefix caching and structured generation by deploying an OpenAI-compatible SGLang server with dependencies including torch and transformers, then applying regex or JSON schema decoding parameters.

Why is my LLM serving slow when generating JSON outputs from repeated few-shot examples?

LLM serving is slow for JSON outputs from repeated few-shot examples because of redundant KV computation, which RadixAttention prefix caching solves by automatically reusing the shared prefix tokens.

When should I not use RadixAttention for structured generation?

Avoid RadixAttention for structured generation when prompt prefixes are largely unique across requests, as the caching mechanism provides no KV computation reduction benefit without shared prefix workloads.