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## News and Updates - **[July 6, 2026]** Guardrails validators are moving to standard PyPI packages you install directly with `pip`, and Guardrails is discontinuing its hosted remote inferencing. See [How to Migrate](https://github.com/guardrails-ai/guardrails/issues/1560) for what to do. **Planned cutoff: August 6, 2026.** - **[Feb 12, 2025]** We just launched Guardrails Index -- the first of its kind benchmark comparing the performance and latency of 24 guardrails across 6 most common categories! Check out the index at index.guardrailsai.com ## What is Guardrails? Guardrails is a Python framework that helps build reliable AI applications by performing two key functions: 1. Guardrails runs Input/Output Guards in your application that detect, quantify and mitigate the presence of specific types of risks. To look at the full suite of risks, check out [Guardrails Hub](https://guardrailsai.com/hub/). 2. Guardrails help you generate structured data from LLMs.

Guardrails in your application

### Guardrails Hub Guardrails Hub is a collection of pre-built measures of specific types of risks (called 'validators'). Multiple validators can be combined together into Input and Output Guards that intercept the inputs and outputs of LLMs. Visit [Guardrails Hub](https://guardrailsai.com/hub/) to see the full list of validators and their documentation.

Guardrails Hub gif

## Installation ```python pip install guardrails-ai ``` ## Getting Started ### Create Input and Output Guards for LLM Validation 1. Download and configure the Guardrails Hub CLI. ```bash pip install guardrails-ai guardrails configure ``` 2. Install a guardrail from Guardrails Hub. ```bash pip install guardrails-ai-regex-match ``` 3. Create a Guard from the installed guardrail. ```python from guardrails import Guard, OnFailAction from guardrails_ai.regex_match import RegexMatch guard = Guard().use( RegexMatch, regex="\(?\d{3}\)?-? *\d{3}-? *-?\d{4}", on_fail=OnFailAction.EXCEPTION ) guard.validate("123-456-7890") # Guardrail passes try: guard.validate("1234-789-0000") # Guardrail fails except Exception as e: print(e) ``` Output: ```console Validation failed for field with errors: Result must match \(?\d{3}\)?-? *\d{3}-? *-?\d{4} ``` 4. Run multiple guardrails within a Guard. First, install the necessary guardrails from Guardrails Hub. ```bash pip install guardrails-ai-competitor-check guardrails-ai-toxic-language ``` Then, create a Guard from the installed guardrails. ```python from guardrails import Guard, OnFailAction from guardrails_ai.competitor_check import CompetitorCheck from guardrails_ai.toxic_language import ToxicLanguage guard = Guard().use( CompetitorCheck(["Apple", "Microsoft", "Google"], on_fail=OnFailAction.EXCEPTION), ToxicLanguage(threshold=0.5, validation_method="sentence", on_fail=OnFailAction.EXCEPTION) ) guard.validate( """An apple a day keeps a doctor away. This is good advice for keeping your health.""" ) # Both the guardrails pass try: guard.validate( """Shut the hell up! Apple just released a new iPhone.""" ) # Both the guardrails fail except Exception as e: print(e) ``` Output: ```console Validation failed for field with errors: Found the following competitors: [['Apple']]. Please avoid naming those competitors next time, The following sentences in your response were found to be toxic: - Shut the hell up! ``` ### Use Guardrails to generate structured data from LLMs Let's go through an example where we ask an LLM to generate fake pet names. To do this, we'll create a Pydantic [BaseModel](https://docs.pydantic.dev/latest/api/base_model/) that represents the structure of the output we want. ```py from pydantic import BaseModel, Field class Pet(BaseModel): pet_type: str = Field(description="Species of pet") name: str = Field(description="a unique pet name") ``` Now, create a Guard from the `Pet` class. The Guard can be used to call the LLM in a manner so that the output is formatted to the `Pet` class. Under the hood, this is done by either of two methods: 1. Function calling: For LLMs that support function calling, we generate structured data using the function call syntax. 2. Prompt optimization: For LLMs that don't support function calling, we add the schema of the expected output to the prompt so that the LLM can generate structured data. ```py from guardrails import Guard import openai prompt = """ What kind of pet should I get and what should I name it? ${gr.complete_json_suffix_v2} """ guard = Guard.for_pydantic(output_class=Pet, prompt=prompt) raw_output, validated_output, *rest = guard( llm_api=openai.completions.create, engine="gpt-3.5-turbo-instruct" ) print(validated_output) ``` This prints: ``` { "pet_type": "dog", "name": "Buddy } ``` ### Guardrails Server Guardrails can be set up as a standalone service served by Flask with `guardrails start`, allowing you to interact with it via a REST API. This approach simplifies development and deployment of Guardrails-powered applications. 1. Install: `pip install "guardrails-ai"` 2. Configure: `guardrails configure` 3. Create a config: `guardrails create --validators=hub://guardrails/two_words --guard-name=two-word-guard` 4. Start the dev server: `guardrails start --config=./config.py` 5. Interact with the dev server via the snippets below ``` # with the guardrails client import guardrails as gr gr.settings.use_server = True guard = gr.Guard(name='two-word-guard') guard.validate('this is more than two words') # or with the openai sdk import openai openai.base_url = "http://localhost:8000/guards/two-word-guard/openai/v1/" os.environ["OPENAI_API_KEY"] = "youropenaikey" messages = [ { "role": "user", "content": "tell me about an apple with 3 words exactly", }, ] completion = openai.chat.completions.create( model="gpt-4o-mini", messages=messages, ) ``` For production deployments, we recommend using Docker with Gunicorn as the WSGI server for improved performance and scalability. ## FAQ #### I'm running into issues with Guardrails. Where can I get help? You can reach out to us on [Discord](https://discord.gg/gw4cR9QvYE) or [Twitter](https://twitter.com/guardrails_ai). #### Can I use Guardrails with any LLM? Yes, Guardrails can be used with proprietary and open-source LLMs. Check out this guide on [how to use Guardrails with any LLM](https://guardrailsai.com/guardrails/docs/how-to-guides/using_llms). #### Can I create my own validators? Yes, you can create your own validators and contribute them to Guardrails Hub. Check out this guide on [how to create your own validators](https://guardrailsai.com/guardrails/docs/how-to-guides/custom_validators). #### Does Guardrails support other languages? Guardrails can be used with Python and JavaScript. Check out the docs on how to use Guardrails from JavaScript. We are working on adding support for other languages. If you would like to contribute to Guardrails, please reach out to us on [Discord](https://discord.gg/gw4cR9QvYE) or [Twitter](https://twitter.com/guardrails_ai). ## Contributing We welcome contributions to Guardrails! Get started by checking out Github issues and check out the [Contributing Guide](CONTRIBUTING.md). Feel free to open an issue, or reach out if you would like to add to the project!