Tool overview
Fabraix is listed under AI Governance Safety & Evaluation AI tools.
What is Fabraix?
Fabraix builds Nyx for autonomous black-box adversarial testing and Arx for runtime defense of AI agents. It tests security, logic, alignment, prompt injection, tool use, and multi-turn failure modes.
Best for
Adversarial testing and runtime defense for AI agents
Who is it for?
Decision note
Rechecked the product, pricing, documentation, security, terms, and current Y Combinator profile. Nyx black-box red teaming, Arx runtime defense, APIs, CI/CD use, a free application-based Research tier, custom Team/Enterprise plans, Google Cloud hosting, configurable retention, Fabraix, Inc., founders@fabraix.com, and 2026 founding were confirmed. A public free trial and affiliate program were not confirmed.
Key features
Runs autonomous black-box red-team scans
Tests security, logic, and alignment weaknesses
Uses more than 1,000 adversarial strategies
Supports CI/CD retesting and continuous coverage
Provides findings dashboards and remediation support
Offers runtime defense APIs through Arx
Use cases
Red-team customer-facing AI agents
Test browser, voice, and multi-agent systems
Measure prompt-injection and tool-use risk
Retest agents after prompt or model changes
Add runtime checks for dangerous actions
Pros
- Requires no source code or model weights for Nyx
- Publishes transparent pricing tiers
- Offers both testing and runtime defense
- Grounded in original adversarial-security research
Cons
- Team and enterprise pricing are custom
- Security findings require engineering remediation
- Continuous testing can add operational cost
Limitations
Continuous testing can add operational cost. Confirm current product scope, security, retention, and commercial terms before deployment.
Pricing details
Billing options
Pricing note
Researchers can apply for $0 non-commercial Nyx access. One-off scans are custom-priced per agent, and continuous coverage is custom-priced monthly by usage. No separate time-limited free trial is published.
Supported languages
- English
Integrations
Agent endpoints
URLs
Phone agents
CI/CD
Nyx API
Arx API



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