Prompt Firewall

A production-ready LLM security firewall powered by Groq. Analyses every prompt in real-time and returns an ALLOW, WARN, or BLOCK verdict before the request reaches your LLM — with full threat reasoning, risk scores, and category breakdowns.

User prompt ──► FirewallProxy ──────────────► Your LLM API
                     │    ▲                        │
                  analyze │ verdict           tool_calls
                     │    │                        │
                     ▼    │                        │
              [Groq LLM Analyzer] ◄────────────────┘
                     │
              ALLOW / WARN / BLOCK

Features

Threat categories

Quick start

1. Install dependencies

pip install -r requirements.txt

2. Configure environment

Copy .env.example to .env and fill in your Groq API key:

cp .env.example .env

GROQ_API_KEY=gsk_...               # required — get yours at console.groq.com
GROQ_MODEL=llama-3.3-70b-versatile # optional
WARN_THRESHOLD=50                  # optional
BLOCK_THRESHOLD=80                 # optional
ANALYZER_TIMEOUT=15                # optional

3. Run

python main.py

  prompt > My SSN is 123-45-6789, help me fill a form

  ⚠️  WARN  score: 65/100  category: pii
  Prompt contains a social security number.

  Severity   Category   Reason
  ────────────────────────────────────────────────
  MEDIUM     pii        SSN pattern detected in prompt

Production usage — FirewallProxy

Wrap any Groq-compatible client to intercept all requests automatically:

from groq import Groq
from firewall import FirewallProxy, FirewallBlockedError, Analyzer

analyzer = Analyzer(
    warn_threshold=50,
    block_threshold=80,
)

client = FirewallProxy(
    Groq(),                      # reads GROQ_API_KEY from env
    analyzer=analyzer,
    on_event=lambda e: print(e), # optional event callback
)

try:
    response = client.chat.completions.create(
        model="llama-3.3-70b-versatile",
        messages=[{"role": "user", "content": "Hello, world!"}],
    )
    print(response.choices[0].message.content)
except FirewallBlockedError as e:
    print(f"Blocked: {e}")

Project layout

prompt-firewall/
├── firewall/
│   ├── __init__.py       # public exports
│   ├── rules.py          # core types: Action, Severity, AnalysisResult
│   ├── analyzer.py       # Groq LLM-based threat analyzer
│   └── proxy.py          # FirewallProxy — wraps any LLM client
├── main.py               # interactive CLI entry point
├── .env                  # local config (git-ignored)
├── .env.example          # config template
└── requirements.txt

Environment variables