Apache-2.0 Python framework wrapping LLM calls in input and output guards built from 65 Hub validators, with a self-hosted REST server.
Python teams that want validation expressed as composable, individually named checks rather than one opaque classifier, since the Hub lists 65 validators including Detect PII (built on Microsoft Presidio), Detect Prompt Injection (built on the Rebuff library), Detect Jailbreak, Llama Guard, Toxic Language, Provenance NLI for grounding, Secrets Present, Web Sanitization and Valid SQL. It also fits teams that need structured output and validation in the same pass, because a Pydantic model drives function calling where the provider supports it and prompt-based schema instructions where it does not. The Guardrails Server exposes guards over REST including an OpenAI-SDK-compatible path, so non-Python callers can reach them.
Ownership changed in 2026: the vendor's own blog announces that Harvey has acquired Guardrails AI and that the founders and team move into Harvey's product and engineering organisation, and that post makes no commitment about the open-source project, the Hub, hosted services, Snowglobe or Guardrails Pro, and gives no sunset dates. The repository's own news item states that validators are moving to standard PyPI packages and that Guardrails is 'discontinuing its hosted remote inferencing' with a cutoff of 25 August 2026, so validators labelled as needing ML or LLM infrastructure must run locally on hardware you provide. No pricing is published anywhere on the site, and no latency figure is published either: the vendor's own validator-latencies post describes its method and hardware but reports only qualitative results, saying remote T4 inference was 'way faster' than local M3 MacBooks without publishing the measurements.
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The vendor's own blog announces that Harvey has acquired Guardrails AI, with co-founders Shreya Rajpal and Zayd Simjee and their team joining Harvey's product and engineering organisation, described there as Harvey's fourth acquisition of 2026. The post makes no commitment about the open-source project, the Hub, hosted services, Snowglobe or Guardrails Pro, and gives no sunset dates for any of them.
Yes on both counts at the time of writing. GitHub reports the licence as Apache License 2.0 and the PyPI metadata for guardrails-ai carries the OSI-approved Apache Software License classifier. Release v0.11.0 shipped in August 2026, commits were pushed in October 2026, supported Python versions run from 3.10 to 3.13, and the repository is not archived. Long-term maintenance after the acquisition is not committed to anywhere.
The repository's news item states that validators are moving to standard PyPI packages and that Guardrails is discontinuing its hosted remote inferencing, with a stated cutoff of 25 August 2026. Validators that the Hub labels as needing ML or LLM infrastructure therefore have to run locally or against an endpoint you supply, which shifts model hosting and the hardware cost onto you rather than the vendor.
Partly. Guardrails AI publishes an AI Guardrails Index covering jailbreaking, PII detection, content moderation, hallucination, competitor check and topic restriction, and it releases its jailbreak dataset publicly as GuardrailsAI/detect-jailbreak on Hugging Face. On the jailbreaking page it calls its own detector the top performer of all guardrails tested, but no F1, true-positive or false-positive figures render on that page, so the claim cannot be verified there.
Facts sourced from the vendor’s own site, last verified 2026-10-10.
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