outlines

Generate schema-conforming JSON, XML, and code outputs from prompts.

Updated Mar 18, 2026
One-click install
npx skills add https://github.com/tadod12/fraud-detection-research --skill outlines-tadod12
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: outlines
Source: https://github.com/tadod12/fraud-detection-research/tree/main/.agent/skills/16-prompt-engineering/outlines
Command: npx skills add https://github.com/tadod12/fraud-detection-research --skill outlines-tadod12

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Outlines provides a robust framework for generating structured outputs (JSON, XML, and code) from natural language prompts, ensuring schema conformance, type-safety, and fast, deterministic results.

Core Features & Use Cases

  • Structured generation: enforce JSON/XML/code formats using JSON schemas and Pydantic models.
  • Type-safe outputs: integrate Pydantic for valid, well-typed results and automatic validation.
  • Local-model support: work with Transformers, vLLM, and llama.cpp without reliance on external APIs.
  • Performance optimization: maximize inference speed with grammar-based generation and FSM-based token filtering.

Quick Start

Ask me to generate a JSON output that strictly conforms to a given schema.

Frequently Asked Questions about outlines

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

FAQPage Schema
How do I enforce structured JSON generation from local models?

Structured JSON generation from local models is enforced by applying grammar-based generation and FSM-based token filtering to guarantee schema-conforming outputs. This framework ensures deterministic results without relying on external APIs.

Can I use Pydantic models for type-safe structured generation with vLLM or llama.cpp?

Yes, Pydantic models integrate seamlessly with vLLM and llama.cpp backends to provide type-safe structured generation. This workflow ensures automatic validation and well-typed results directly from local-model inference.

What is the best way to guarantee LLM outputs conform to a JSON schema?

The best way to guarantee JSON schema conformance is using grammar-based generation with FSM-based token filtering. This approach forces the model to produce valid, schema-conforming structured outputs deterministically during inference.

Does structured generation work with Transformers, vLLM, and llama.cpp backends?

Yes, structured generation works with Transformers, vLLM, and llama.cpp backends. It supports local-model workflows natively, allowing you to enforce JSON, XML, and code formats without reliance on external APIs.

Why do I need grammar-based generation for type-safe prompt engineering?

Grammar-based generation is needed for type-safe prompt engineering because it uses FSM-based token filtering to constrain outputs to valid JSON schemas or Pydantic models. This guarantees deterministic, fast inference and seamless validation.