secretgate 0.1.0

Lean security proxy for AI coding tools — scan and redact secrets before they reach LLM APIs

secretgate

A lean security proxy for AI coding tools. Routes all LLM API traffic through a local proxy that scans for secrets before they leave your machine.

Architecture

IDE / CLI / Agent
       │
       ▼
┌──────────────────────────┐
│     secretgate :8082     │
│                          │
│  ┌────────────────────┐  │
│  │  Secret Scanner    │  │
│  │  (regex + entropy) │  │
│  ├────────────────────┤  │
│  │  Pipeline Steps    │  │
│  │  (pluggable)       │  │
│  ├────────────────────┤  │
│  │  Audit Logger      │  │
│  └────────────────────┘  │
│                          │
│  Reverse proxy per       │
│  provider, streaming     │
└───────────┬──────────────┘
            │
            ▼
      LLM Provider APIs
      (OpenAI, Anthropic, Ollama, ...)

How it works

1. Configure your AI tool to point at secretgate as its API base URL
2. secretgate intercepts every outbound request and scans all messages for secrets
3. Detected secrets are handled based on the mode:
   • redact: replace with REDACTED<aws-access-key:a1b2c3d4e5f6> placeholders before forwarding
   • block: reject the request entirely
   • audit: log and forward unchanged (good for testing)
4. On the response path, redacted placeholders are restored to their original values
5. Everything is logged for audit

Placeholders are deterministic and self-documenting — same secret always produces the same placeholder, and the type identifier tells the LLM what kind of secret was redacted without exposing the value.

Quickstart

pip install secretgate
secretgate serve                          # start on :8080, redact mode
secretgate serve --port 8082 --mode audit # audit mode (log only, don't modify)
secretgate serve --mode block             # block requests containing secrets

Using with Claude Code

# Terminal 1: start the proxy
secretgate serve --port 8082 --mode audit

# Terminal 2: start Claude Code through the proxy
ANTHROPIC_BASE_URL=http://localhost:8082/anthropic claude

This routes all Claude Code API traffic through secretgate. Requires an API key (ANTHROPIC_API_KEY) — OAuth-based login uses a different endpoint that requires HTTPS proxy / TLS MITM (not yet supported).

What you'll see in the logs:

[info     ] request                        messages=19 model=claude-opus-4-6
[warning  ] secret_detected                line=93 pattern='API Key' service=Anthropic
[warning  ] secret_detected                line=99 pattern='AWS Access Key' service=Amazon
[warning  ] secret_detected                line=100 pattern='high-entropy value (Key)' service=entropy
[warning  ] secrets_audit_only             secrets_found=3

Secrets in conversation history (from previous assistant responses) are caught on the next turn when they become part of the outbound request.

Using with other AI tools

# OpenAI-compatible tools (Cursor, Continue, etc.)
export OPENAI_BASE_URL=http://localhost:8082/openai

# Anthropic-compatible tools
export ANTHROPIC_BASE_URL=http://localhost:8082/anthropic

# Ollama
export OLLAMA_HOST=http://localhost:8082/ollama

Modes

Mode	Behavior	Use case
redact	Replace secrets with placeholders, restore on response	Production use
block	Reject requests containing secrets (HTTP 403)	Strict environments
audit	Log secrets but forward request unchanged	Testing, evaluation

Extra detection with detect-secrets

For broader coverage, enable Yelp's detect-secrets as a supplementary scanner (23 additional regex plugins, entropy detectors disabled to avoid false positives):

pip install secretgate[detect-secrets]
secretgate serve --detect-secrets

Or via environment variable:

export SECRETGATE_DETECT_SECRETS=true

Offline scanning

Scan files or stdin for secrets without running the proxy:

secretgate scan .env config.yaml          # scan specific files
cat .env | secretgate scan                # scan stdin
git diff --cached | secretgate scan       # scan staged changes
secretgate scan --no-entropy src/         # regex-only (fewer false positives)

Adding custom secret patterns

Drop patterns in ~/.secretgate/signatures.yaml or pass --signatures /path/to/file.yaml.

- MyCompany:
    - Internal API Key: "myco_[a-zA-Z0-9]{32}"
    - Database URL: "postgres://.*@prod\\.mycompany\\.com"

Development

git clone https://github.com/secretgate/secretgate.git
cd secretgate
python3 -m venv .venv && source .venv/bin/activate
pip install -e ".[dev]"
pre-commit install

# Run tests
pytest tests/ -v

# Lint
ruff check src/ tests/

Pre-commit hooks

secretgate includes pre-commit hooks for development. After pip install -e ".[dev]":

pre-commit install

This enables ruff lint/format, trailing whitespace fixes, and secretgate's own secret scanner on staged files.

License

Apache 2.0