Rebuff vs Guardrails: Which One Covers More of the OWASP LLM Top 10 in 2026?
Rebuff and Guardrails are both open-source Guardrails / LLM Firewall tools, diffed on license, language, maintainer, and repository status as of 2026-07-13. Both fit teams evaluating guardrails / llm firewall; the real difference is language, maintenance activity, and scope — not feature count.
Sponsored Comparison — this slot is available to category sponsors. Paid placement does not alter the coverage data or verdict below.
Spec comparison
| Attribute | Rebuff | Guardrails |
|---|---|---|
| Maintainer | Protect AI (a Palo Alto Networks company) | Guardrails AI |
| License | Apache-2.0 | Apache-2.0 |
| Language | TypeScript | Python |
| Status | Archived | Active |
| Primary use | LLM prompt injection detector using heuristics, an LLM-based detector, vector-store similarity, and canary tokens | Framework for adding structural, type, and quality guardrails to LLM outputs, including input/output validators for security risks like prompt injection and PII leakage |
Read the full profiles: Rebuff, Guardrails.
Last verified . Sources: https://github.com/protectai/rebuff, https://github.com/guardrails-ai/guardrails. Funding and repo figures are third-party and go stale. Re-verify before you rely on them.
Informational, not professional security advice — verify both projects' claims against OWASP, MITRE, and the maintainers directly before a decision. OWASP, MITRE, and the listed vendors and maintainers do not endorse llmthreat.com.