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noamgat avatar

noamgat/lm-format-enforcer

0
View on GitHub↗
2,022 stars·91 forks·Python·MIT·28 views

Lm Format Enforcer

This library provides a framework for enforcing structural constraints on language model output during the token generation process. It functions as middleware that restricts model responses to strictly adhere to predefined JSON schemas or regular expression patterns, ensuring that generated text is machine-readable and consistent for downstream data consumption.

The project distinguishes itself by integrating directly with inference engines to intercept token probability distributions before the final sampling stage. By utilizing state-machine parsing and recursive schema decomposition, it performs lookahead validation to prune invalid token sequences. This approach allows for precise control over output, including the enforcement of specific field ordering within JSON objects and the ability to handle multiple concurrent generation streams through batched constraint execution.

The library supports a wide range of integration strategies, allowing it to function across diverse model backends and inference server environments. It includes diagnostic tools for analyzing the performance impact of these constraints, ensuring compatibility and efficiency across different hardware setups. The software is distributed as a Python package designed for integration into existing inference pipelines.

Features

  • Structured Output Generators - Ensures language models produce text that strictly follows predefined JSON schemas or regular expression patterns.
  • Output Constraint Engines - Restricts token generation during inference to ensure adherence to JSON schemas or regular expression patterns.
  • Inference Middleware - Provides a standardized middleware layer to intercept and modify token probability distributions across diverse model backends.
  • Output Constraint Engines - Enforces strict JSON schema adherence during token generation by intercepting probability distributions to prune invalid sequences.
  • Schema Enforcement Tools - Validates and forces language model outputs to adhere to specific data structures during inference.
  • Logit Masks - Filters model vocabulary at each generation step by masking tokens that violate structural constraints.
  • LLM Output Constraints - Restricts language model token generation to strictly follow defined JSON schemas and regular expression patterns.
  • Generation State Machines - Maintains a deterministic state machine to track schema positions and validate next-token candidates.
  • Data Extraction Pipelines - Builds robust workflows for generating machine-readable data from language models.
  • Regex Constraint Engines - Provides regex-based token masking to ensure generated text matches specific patterns for downstream data consumption.
  • LLM Inference Engines - Connects output enforcement logic to various model execution backends.
  • Batch Generation - Applies independent token constraints to multiple concurrent inputs during a single generation process.
  • Regex-Based Output Filters - Limits language model output to match precise regular expression patterns for predictable data consumption.
  • Parser Combinators - Merges distinct parsing logic into a unified workflow to process complex data structures.
  • Generation Lookaheads - Prunes invalid token sequences by simulating potential future outputs to ensure structural compliance.
  • Inference Engine Integrations - Provides a framework for applying structural output constraints across various model backends.
  • Schema Decomposition - Decomposes complex data structures into manageable parsing rules evaluated incrementally during generation.
  • Generation Stream Batching - Enables efficient handling of multiple concurrent generation streams by maintaining separate parser states for each request.

Star history

Star history chart for noamgat/lm-format-enforcerStar history chart for noamgat/lm-format-enforcer

How this analysis was created: This summary and feature list are AI-generated from collected project material and can contain mistakes. Stars, license and language are imported from GitHub. Inclusion does not mean that we have tested or audited this project. Check the source documentation for any feature you depend on. Learn more on our About page.

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Frequently asked questions

What does noamgat/lm-format-enforcer do?

This library provides a framework for enforcing structural constraints on language model output during the token generation process. It functions as middleware that restricts model responses to strictly adhere to predefined JSON schemas or regular expression patterns, ensuring that generated text is machine-readable and consistent for downstream data consumption.

What are the main features of noamgat/lm-format-enforcer?

The main features of noamgat/lm-format-enforcer are: Structured Output Generators, Output Constraint Engines, Inference Middleware, Schema Enforcement Tools, Logit Masks, LLM Output Constraints, Generation State Machines, Data Extraction Pipelines.

Which projects share features with noamgat/lm-format-enforcer?

Projects with overlapping indexed features include: eth-sri/lmql — LMQL is a programming language and probabilistic interface that blends algorithmic logic with stochastic text… dottxt-ai/outlines — Outlines is a library designed to ensure machine-readable output from generative models by applying programmatic… microsoft/guidance — Guidance is a control framework and generation orchestrator for large language models. It provides a programming layer… outlines-dev/outlines — Outlines is a guided text generation framework and structured output engine for large language models. It enforces… boundaryml/baml — BAML is a prompt engineering framework and LLM client generator that defines AI prompts as type-safe functions. It… abetlen/llama-cpp-python — llama-cpp-python provides a Python interface for the llama.cpp library, enabling the execution of large language…

Projects sharing features with Lm Format Enforcer

These projects share indexed features with Lm Format Enforcer. Shared tags can include platform or build tooling; verify the primary use case before treating a result as a replacement.
  • eth-sri/lmqleth-sri avatar

    eth-sri/lmql

    4,185View on GitHub↗

    LMQL is a programming language and probabilistic interface that blends algorithmic logic with stochastic text generation. It functions as a constraint-guided prompting framework and structured output generator, allowing users to force model responses to adhere to strict formatting and data types. The system distinguishes itself as an inference optimizer that increases token throughput and reduces latency. This is achieved through specialized execution strategies, including tree-based prompt caching and asynchronous batch processing. The project covers a broad range of generation control capa

    Python
    View on GitHub↗4,185
  • dottxt-ai/outlinesdottxt-ai avatar

    dottxt-ai/outlines

    13,446View on GitHub↗

    Outlines is a library designed to ensure machine-readable output from generative models by applying programmatic constraints during the token sampling process. It functions as a toolkit for forcing large language models to generate text that strictly adheres to JSON schemas, regular expressions, and formal grammars, enabling the integration of model responses into existing software systems. The library distinguishes itself by integrating formal language rules directly into the sampling loop. It achieves this by converting regular expressions into deterministic finite automata and utilizing lo

    Pythoncfggenerative-aijson
    View on GitHub↗13,446
  • microsoft/guidancemicrosoft avatar

    microsoft/guidance

    21,502View on GitHub↗

    Guidance is a control framework and generation orchestrator for large language models. It provides a programming layer to steer model outputs through structured templates, schema enforcement, and logical flow management. The framework distinguishes itself by interleaving model generation with local code execution, enabling the use of loops and conditional branching within a single session. It employs grammar-based token constraints and regular expressions to force models to sample only from tokens that satisfy a specific structural format, ensuring strict adherence to predefined data models.

    Jupyter Notebook
    View on GitHub↗21,502
  • outlines-dev/outlinesoutlines-dev avatar

    outlines-dev/outlines

    13,965View on GitHub↗

    Outlines is a guided text generation framework and structured output engine for large language models. It enforces precise structural constraints on model output during the sampling process to ensure the generation of valid data. The framework ensures that model outputs strictly adhere to predefined data models, including JSON schemas, regular expressions, and formal grammars. This enables the conversion of natural language inputs into structured arguments for function calling and the generation of valid JSON for downstream processing. The system manages model orchestration through prompt te

    Python
    View on GitHub↗13,965
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Curated searches featuring Lm Format Enforcer

Hand-picked collections where Lm Format Enforcer appears.
  • LLM Structured Output Libraries
  • Typed LLM Orchestration Frameworks