outlines

Generate structured text from language models using Pydantic, JSON schemas, or regex.

Updated Mar 8, 2026
One-click install
npx skills add https://github.com/helix4u/hermes-agent-private --skill outlines-helix4u
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: outlines
Source: https://github.com/helix4u/hermes-agent-private/tree/main/skills/mlops/outlines
Command: npx skills add https://github.com/helix4u/hermes-agent-private --skill outlines-helix4u

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires outlines, transformers, vllm, pydantic, and includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill guarantees that AI-generated text conforms to specific structures like JSON, XML, or regex patterns, preventing errors and ensuring data integrity.

Core Features & Use Cases

  • Structured Output: Generate valid JSON, XML, or code that strictly adheres to defined schemas or grammars.
  • Type Safety: Use Pydantic models for robust, type-checked data generation.
  • Local Model Support: Maximize inference speed and control by running models locally (Transformers, vLLM, llama.cpp).
  • Use Case: Automatically extract user profile data from unstructured text into a Pydantic model, ensuring all fields (name, age, email) are correctly formatted and present.

Quick Start

Use the outlines skill to generate a JSON object representing a user with name, age, and email.

Frequently Asked Questions about outlines

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

FAQPage Schema
How do I force an LLM to generate valid JSON output?

To force an LLM to generate valid JSON, you can use constrained decoding to enforce output schemas. This guarantees that generated text strictly adheres to defined structures, preventing malformed data and ensuring integrity.

Can I use Pydantic models for structured generation with local models?

Yes, you can use Pydantic models for structured generation with local models. This approach provides type safety and robust data validation while running inference locally using frameworks like Transformers, vLLM, or llama.cpp.

What is the best way to extract structured data from unstructured text using a local model?

The best way to extract structured data is by applying grammar-based generation to constrain local model outputs. You define a Pydantic model or JSON schema, and the model deterministically fills the required fields from unstructured text.

How do I enforce a regex pattern when generating text with an LLM?

You can enforce a regex pattern during LLM text generation by applying constrained decoding. This restricts the model's vocabulary space at each step, ensuring the final output strictly matches your specified regular expression grammar.

Does constrained decoding work with vLLM and transformers?

Yes, constrained decoding works with both vLLM and transformers. These local model serving frameworks are explicitly supported, allowing you to maximize inference speed and control while maintaining strict output schema adherence.

Why do I get malformed JSON when using large language models?

Malformed JSON occurs because standard LLMs generate text probabilistically without structural awareness. Applying grammar-based constrained decoding enforces strict output schemas, eliminating formatting errors and guaranteeing valid JSON generation.