Get Your First Proof in 5 Minutes

Get Your API Key

Request a free API key. Free tier gives you 100 proofs per month — no credit card required. We'll email your key within 24 hours.

Once you have it, set it as an environment variable:

export SENTINEL_API_KEY="your_api_key_here"

Check the API Is Up

Verify the SENTINEL API is healthy (no authentication required):

curl https://api.starksentinel.com/health

You should see:

{
  "status": "healthy",
  "version": "1.1.0",
  "timestamp": "2026-04-02T12:00:00.000Z"
}

Generate a Proof

Send behavioral observations to the /v1/prove endpoint. In this example, we're attesting that an AI agent's quality scores stay within control limits:

curl -X POST https://api.starksentinel.com/v1/prove \
  -H "X-API-Key: $SENTINEL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "observations": [95, 98, 92, 97, 100, 94, 96, 99],
    "baseline_mean": 96,
    "ucl": 110,
    "lcl": 80
  }'

The response arrives in ~9ms:

{
  "public_inputs": {
    "num_observations": 8,
    "baseline_mean": 96,
    "final_ewma": 95,
    "ucl": 110,
    "lcl": 80,
    "within_limits": true
  },
  "proof_bytes": "base64-encoded-stark-proof...",
  "metadata": {
    "generation_time_ms": 9,
    "proof_size_bytes": 6761,
    "security_level": 96
  }
}

Notice: the response contains no raw observation values. The proof attests to the statistical result (EWMA within limits) without revealing the underlying data. This is the Prove-Don't-Share architecture.

Verify the Proof

Pass the proof_bytes and public_inputs from the prove response to /v1/verify. Verification is always free and unlimited.

curl -X POST https://api.starksentinel.com/v1/verify \
  -H "X-API-Key: $SENTINEL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "proof_bytes": "PASTE_PROOF_BYTES_HERE",
    "public_inputs": {
      "num_observations": 8,
      "baseline_mean": 96,
      "final_ewma": 95,
      "ucl": 110,
      "lcl": 80,
      "within_limits": true
    }
  }'

A valid proof returns:

{
  "valid": true,
  "public_inputs": {
    "num_observations": 8,
    "baseline_mean": 96,
    "final_ewma": 95,
    "ucl": 110,
    "lcl": 80,
    "within_limits": true
  },
  "metadata": {
    "verification_time_ms": 2
  }
}

Read the Public Inputs

The public_inputs object tells the story in plain integers — no cryptography PhD required:

This is what you share with auditors, clients, and regulators. The cryptographic proof guarantees these numbers are authentic — but the numbers themselves are human-readable.