LLMs can generate valid JSON 100% of the time
Outlines is a Python library that focuses on text generation with large language models. Brandon and I are not LLM experts and started the project a few months ago because we wanted to understand better how the generation process works. Our original background is probabilistic, relational and symbolic programming. Recently we came up with a fast way to generate text that matches a regex (https://blog.normalcomputing.ai/posts/2023-07-27-regex-guide...). The basic idea is simple: regular expressions have an equivalent Deterministic-Finite Automaton (DFA) representation. We…
LLMs can generate valid JSON 100% of the time launched on August 14, 2023 with 854 votes, #6 of 4,347 launches that month and more than 99% of that year's launches. The site was still online in September 2026, 3 years on.
In plain words
Outlines is a Python library for controlling text generation with large language models. It enables users to generate text that matches specific patterns, such as regular expressions, by converting those patterns into finite automaton representations and using them to guide the model's token selection. The library is designed for developers who need structured, validated outputs from language models.
written from the facts on this page · September 2026
From the sources
Structured Outputs. Contribute to dottxt-ai/outlines development by creating an account on GitHub.
In the maker’s words, at launch
Outlines is a Python library that focuses on text generation with large language models. Brandon and I are not LLM experts and started the project a few months ago because we wanted to understand better how the generation process works. Our original background is probabilistic, relational and symbolic programming.…
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