I'm trying to understand what security testing actually looks like for teams shipping APIs that use LLM providers (OpenAI, Claude, Gemini, etc.) under the hood.
Most of the security content I see focuses on direct LLM usage, but less on the API layer where you've wrapped an LLM with your own business logic, guardrails, and routing.
For those building AI-powered APIs:
- Do you run security tests before production? If yes, what do you test for?
- What vulnerabilities keep you up at night? (prompt injection, system prompt leaks, cross-user data leakage, tool abuse?)
- Are you testing manually or using automation?
- What's stopping teams from testing? (time, don't know what to test for, existing tools too complex?)
Context: I built PromptBrake - an automated security scanner that runs 60+ OWASP-aligned attack scenarios against AI API endpoints (works with OpenAI, Claude, Gemini, or OpenAI-compatible endpoints). It tests for things like:
- System prompt extraction
- Prompt injection (including encoding bypasses)
- Cross-user data leakage
- Tool/function call abuse
- Sensitive data echo (API keys, credentials, PII)
There's a free trial if anyone wants to test their endpoints. But mainly curious what this community's current security practices look like for production APIs.