Best Prompt Injection Protection 2026
Prompt injection can make an agent do what an attacker wants — including spend. Defense-in-depth: detection tools plus a deterministic spend layer.
Detection tools
Lakera — injection detection API, low-latency.
Robust Intelligence (Cisco) — model security and red-teaming.
Prompt Security — firewall for prompt attacks.
Aporia — LLM security monitoring.
Their limits
Detection is probabilistic — a bypass is always possible.
Even a detected injection still needs something to STOP the money from moving.
The deterministic layer
sipi.bot's decision path is a rules engine — no model to inject. An attacker can't talk a merchant allowlist into approving an unknown vendor.
At a glance
| Tool | Approach | Spend-safe? |
|---|---|---|
| Lakera | Detection API | No — detects, doesn't gate |
| Robust Intelligence | Model security | No |
| Prompt Security | Prompt firewall | No |
| sipi.bot | Deterministic rules | Yes — blocks before settlement |
FAQ
Is sipi.bot prompt-injection protection?
It's the layer injection can't bypass: a deterministic rules engine. Detection tools catch attacks; sipi.bot makes the damage impossible regardless.
Should I replace detection tools with sipi.bot?
No — defense in depth. Detect with one, gate spend with sipi.bot.
Can an injected instruction approve a purchase?
No — approvals come from rules, not from the model. An unknown merchant stays BLOCKED.
Related
Stop the next $12,400 night.
One API call (or MCP tool) in front of every agent transaction — APPROVED, BLOCKED, or FLAGGED, deterministic, ~5 ms, fully logged.
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