CAIN-42 CAIN StudioHow CAIN-42 compares · AI security & scanners
CAIN-42 vs Promptfoo
An open-source tool for testing, red-teaming and evaluating LLM apps and agents, with a large library of attack plugins and CI integration.
What Promptfoo does well
- Free and open source with broad community adoption.
- Rich red-team plugins and dataset-driven evaluations.
- Easy CI integration for prompt and agent testing.
What CAIN-42 does differently
- Enforces at the tool-call boundary, before anything runs.
- Orders authorization through a Byzantine quorum (3-of-4): one "yes" is never enough.
- Leaves a per-action signed receipt you can verify offline with a clean-room verifier.
- Authority continuity: a change to the model, tool, memory, skill or delegation forces a re-check.
- Self-serve from $19.75/mo; runs hosted, self-hosted or air-gapped.
Capability difference
| Capability | CAIN-42 | Promptfoo | Source (verified 2026-10-14) |
|---|---|---|---|
| Primary focus | Runtime governance in the execution path | Test-time red-teaming and evaluation | Promptfoo source page verified 2026-10-14 |
| Blocks the tool call at the boundary | Yes — MCPGate halts before the tool runs | No (test-time, not runtime enforcement) | |
| Byzantine-ordered authorization (quorum cert) | Yes — 3-of-4 PBFT quorum certificate | No* | |
| Per-action signed receipt, offline-verifiable | Yes — Ed25519, hash-chained, offline-verifiable | No* | |
| Runtime enforcement | Yes | No (pre-deployment testing) | |
| Public entry price | $19.75/mo self-serve | Free / OSS |
When to pick which
Pick Promptfoo to test and red-team before you ship. Pick CAIN-42 to enforce and record at run time, after the test is done.
Based on each vendor's public homepage and product pages, last reviewed 2026-10-14. No affiliation and no claim about their internals. "No*" means we found no public documentation of that capability, not that the vendor cannot do it.