Identity verification for people and their agents

Prove you're human. Empower your agents.

Proof gives individuals and organizations a cryptographic human presence token — verified by identity verification — so your AI agents can prove they're acting on behalf of a real person. Liveness detection, anti-spoofing, and a simple API.

Free tier included · No credit card required

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Verification latency

6 SDKs

Every platform covered

BIPA/GDPR

Compliance-ready

MCP

AI agent protocol

Everything you need — whether you're a solo developer or an enterprise

A complete platform for identity verification. Give your AI agents a human presence token, or build identity verification into your product.

Built for AI Agents

MCP server for Claude, Cursor, and any MCP-compatible client. Request human presence verification before high-value actions — with org-scoped API key billing.

5-Check Verification Pipeline

Liveness detection, frame consistency, impossible travel, embedding history, and device fingerprinting. Four robustness levels from basic to maximum security.

Privacy & Consent Built In

Irreversible embeddings — never raw images. AES-256-GCM encryption at rest with per-org keys. BIPA/GDPR/CCPA audit trails with timestamped consent records. Consent revocation triggers full data deletion.

API, SDKs & Federation

Six official SDKs (TypeScript, Python, Go, iOS, Android, React Native). OAuth 2.0/OIDC server, SCIM 2.0 provisioning, HMAC-signed webhooks, and IAM.

Human Presence Token

Signed JWT with biometric confidence scores, anti-replay nonce, and purpose field. Tamper-evident and auditable — short-lived tokens expire automatically.

Passwordless Admin Portal

Fully passwordless admin auth — passkeys, face biometrics, or face+voice multimodal. Real-time analytics, IAM, audit logs, billing, and multi-tenant RBAC.

For individuals

Your agents deserve a real identity

AI agents are only as trustworthy as the person behind them. Proof lets you enroll once, then issue human presence tokens that your agents present whenever they need to prove a real person authorized their actions.

  • Let your agents transact, sign, and communicate with verified trust
  • One enrollment — works across all your agents and tools
  • Privacy-preserving: only an irreversible embedding is stored, never your photo
Get your human presence token

You

issues token to

Agent 1

Agent 2

Agent 3

Each agent carries your verified human presence token

See the API in action

One API call to verify. One token to prove it.

POST /api/verify
curl -X POST /api/verify \
  -H "X-API-Key: nxid_live_abc123..." \
  -H "Content-Type: application/json" \
  -d '{
    "email": "user@example.com",
    "image": "<base64-selfie>"
  }'
200 OKResponse
{
  "match": true,
  "confidence": 0.97,
  "robustness": "high",
  "humanPresenceToken": "eyJhbGciOiJF...",
  "checks": {
    "liveness": "pass",
    "antispoofing": "pass",
    "impossibleTravel": "pass",
    "frameConsistency": "pass",
    "embeddingHistory": "pass"
  }
}

Decoded Human Presence Token

{
  "sub": "a1b2c3d4e5f6a1b2c3d4e5f6a1b2c3d4",
  "iss": "proof",
  "iat": 1712400000,
  "exp": 1712403600,
  "nid:userId": "clx9...",
  "nid:emailHash": "7f3a1b2c4d5e6f78",
  "nid:purpose": "api-verify",
  "nid:nonce": "a1b2c3d4e5f6",
  "nid:robustness": "high",
  "nid:checks": {
    "compositeScore": 0.97,
    "liveness": 0.99,
    "frameConsistency": 0.95
  }
}

Tamper-evident

Signed JWT — any modification invalidates the token

Anti-replay

Unique nonce prevents token reuse across sessions

Auditable

Every verification logged with timestamps and scores

Short-lived

Configurable TTL — tokens expire automatically

Simple, transparent pricing

Start free. Scale when you're ready.

Most popular

Free

$0/ month

No credit card required

  • 50 verifications / month
  • 10 enrollments / month
  • 5-check verification pipeline (face + voice)
  • Human presence tokens for AI agents
  • MCP server for Claude, Cursor & more
  • 6 SDKs — TypeScript, Python, Go, iOS, Android, React Native
  • OAuth 2.0/OIDC & SCIM 2.0
  • Passwordless admin auth
  • BIPA/GDPR/CCPA compliance
Get started free

Pay as you go

$0.05/ verification

$0.10 per enrollment · $1.00 per active user/mo

  • Unlimited verifications
  • Unlimited enrollments
  • Everything in Free, plus:
  • HMAC-signed webhooks
  • Priority support
  • Custom verification profiles
  • Advanced analytics & audit trails
  • Multi-admin RBAC & IAM
  • Volume discounts available
Start with free tier

Ready to give your agents a human identity?

Whether you're an individual with AI agents or an enterprise securing access, get started in minutes. No credit card required.