outlines

Generate JSON/Pydantic outputs from natural prompts using grammar-constrained local models.

31|3|Updated May 7, 2026
One-click install
npx skills add https://github.com/markwang2658/hermes-windows-native --skill outlines-markwang2658
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: outlines
Source: https://github.com/markwang2658/hermes-windows-native/tree/main/hermes-agent/optional-skills/mlops/inference/outlines
Command: npx skills add https://github.com/markwang2658/hermes-windows-native --skill outlines-markwang2658

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Outlines enables developers to generate structured, type-safe outputs (JSON/Pydantic) from natural prompts using local model backends and grammar-based constraints to ensure validity.

Core Features & Use Cases

  • Structured generation via JSON schemas and Pydantic models to ensure valid outputs
  • Local backends support (Transformers, llama.cpp, vLLM) for zero-dependency production
  • Use cases include data extraction, form-like data generation, and code/document generation

Quick Start

Provide a natural language prompt that yields a JSON-compatible object conforming to a given Pydantic model.

Frequently Asked Questions about outlines

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

FAQPage Schema
How do I generate valid JSON from a local model using a Pydantic schema?

To generate valid JSON from local models, you apply Pydantic models or JSON schemas as grammar-based constraints to your natural language prompts. This guarantees type-safe, structured outputs that conform exactly to your specified schema.

What is grammar-based structured generation for local LLMs?

Grammar-based structured generation applies schema constraints during text generation to enforce type-safe, valid outputs from local LLMs. This mechanism forces the model to generate valid JSON or Pydantic objects instead of unstructured text.

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

Yes, structured generation works with llama.cpp and vLLM local backends. It also supports Transformers and optional OpenAI integration, allowing you to enforce Pydantic or JSON schema constraints across multiple local model serving environments.

Can I use Pydantic constraints for data extraction with local models?

Yes, you can use Pydantic constraints for data extraction with local models. By defining a Pydantic model, you can extract structured, form-like data from natural language prompts while guaranteeing the output remains type-safe and valid.

Do I need a Python environment to enforce JSON schema during LLM generation?

Yes, you need a Python environment with the outlines package and your chosen local backends installed. This Python setup is required to apply JSON schema constraints and execute grammar-based generation workflows locally.