How is Proof of Holdings different from Twilio Verify?

Twilio Verify sends a code TO the user via SMS, voice, or push notification. Proof of Holdings uses Reverse OTP — the user sends a code TO the service via Telegram, WhatsApp, or . This eliminates delivery failures (0% vs 10-30% for international SMS), prevents SIM-swap attacks, and produces a cryptographic proof token that can be verified offline. Twilio only verifies phone and email. Proof of Holdings verifies phone, email, domain, wallet, and social accounts — all from one API.

Is Proof of Holdings more affordable than Twilio?

Yes. Twilio charges $0.05 per successful verification plus channel-specific fees (SMS costs extra). Proof of Holdings starts at €0.0079 per proof on the Business plan, with 300 free proofs per month on Pay As You Go. One proof covers ANY asset type — phone, email, domain, wallet, or social — at the same price. With Twilio, you'd need separate services for domain and wallet verification.

Does Twilio support domain or wallet verification?

No. Twilio Verify only supports phone numbers and email addresses. For domain verification (DNS TXT, HTTP file, admin email) or crypto wallet verification (Ethereum, Solana, Bitcoin, etc.), you'd need additional services. Proof of Holdings handles all 5 asset types from one API with one pricing model.

What are proof tokens?

Every verification on Proof of Holdings produces an RS256-signed JWT token. This token cryptographically proves that a specific asset (phone, email, domain, wallet, or social account) was verified at a specific time. You can verify the token offline using our public key — no API call needed. Twilio returns a verification status (success/fail) but no portable cryptographic proof. Proof tokens can be shared with third parties, stored for compliance, or validated by automated systems.

Does Twilio have human-in-the-loop approvals?

Twilio has Verify Push, which sends approve/deny push notifications. However, it requires building a mobile app with Twilio's SDK, and doesn't produce cryptographic proof of the decision. Proof of Holdings delivers approval requests via Telegram or WhatsApp (no app required), and every approve/deny decision produces a signed proof token with the user's response.

Can I use Proof of Holdings with AI agents?

Yes. Proof of Holdings has a dedicated MCP server with 131 tools that works with Claude, LangChain, CrewAI, and any MCP-compatible agent framework. AI agents can create verifications, request human approvals, and validate proof tokens programmatically. Twilio has an alpha MCP server with limited capabilities.

Comparison

Proof of Holdings vs Twilio Verify

Q: What is Reverse OTP and why does it matter?

Traditional OTP sends a code FROM the service TO the user. If the SMS doesn't arrive (10-30% failure rate internationally), verification fails. Reverse OTP flips the flow: the user sends a code TO the service via Telegram, WhatsApp, or . Since the user initiates the message, there are zero delivery failures. It's also immune to SIM-swap attacks because the attacker would need access to the actual messaging app, not just the phone number.

Twilio verifies phone numbers with SMS OTP. Proof of Holdings verifies control of any digital asset — phone, email, domain, wallet, social — using Reverse OTP with cryptographic proof tokens. No identity documents needed.

Feature Comparison

Feature	Proof of Holdings	Twilio Verify
Phone verification	Telegram, WhatsApp, SMS	SMS, Voice, Push, SNA
Email verification	Magic Link, OTP	OTP
Domain verification	DNS TXT, HTTP, Admin Email, Auto-Verify
Wallet verification	8 chains (ETH, SOL, BTC, BNB, COSMOS, TRON, ADA, HBAR)
Social verification	12+ platforms (GitHub, Google, LinkedIn, X, etc.)
Reverse OTP
Cryptographic proof tokens	RS256 JWT, offline-verifiable
Human-in-the-loop approvals	Telegram/WhatsApp with proof tokens	Push (requires your mobile app)
MCP server for AI agents	131 tools	Alpha (limited)
Delivery failure rate	0% (user-initiated)	10-30% internationally
SIM-swap resistant
Free tier	300 proofs/month
Identity documents required

10-30%

SMS failure internationally (Twilio)

30+

Verification channels (Proof)

Security

SIM-swap attacks are the biggest vulnerability of SMS OTP. An attacker convinces a carrier to transfer the victim's number to a new SIM, then receives all SMS codes. Twilio Verify is vulnerable to this attack vector.

Proof of Holdings is immune to SIM-swap attacks because Reverse OTP requires the user to send a message FROM their Telegram, WhatsApp, or account. An attacker would need to compromise the actual messaging application, not just the phone number.

Every Proof of Holdings verification produces an RS256-signed JWT proof token that can be verified offline using our published public key. No API call needed. Twilio returns a status flag (verified/unverified) with no cryptographic attestation.

Proof Tokens

When verification completes on Proof of Holdings, you receive an RS256-signed JWT token. This token proves:

Which asset was verified (phone number, email, domain, wallet, social account)
When the verification happened
That the proof hasn't been tampered with

The token can be verified offline using the public key. Share it with partners, store it for compliance, or validate it in automated pipelines without contacting the Proof API.

Twilio Verify returns a verification status. There is no portable proof that verification occurred.

AI Agent Integration

Proof of Holdings has a dedicated MCP server with 131 tools covering verification, human approvals, asset management, proof validation, billing, and more. Works with Claude, LangChain, CrewAI, OpenAI Agents SDK, and any MCP-compatible framework.

Human-in-the-loop approvals let AI agents request human permission before irreversible actions. The human receives the request via Telegram or WhatsApp, taps Approve or Deny, and the decision is returned as a signed proof token.

Twilio released an alpha MCP server in March 2025 with limited capabilities. Twilio Push can send approve/deny notifications but requires your own mobile app with their SDK, and doesn't produce cryptographic proof of the decision.

When to use Twilio Verify

You only need phone or email OTP and are targeting US/Canada where SMS delivery is reliable
You already use the Twilio ecosystem (Programmable SMS, Voice, etc.) and want unified billing
You need Silent Network Authentication (carrier-level zero-interaction verification)
Your users don't have Telegram, WhatsApp, or (rare internationally, common in some US demographics)

When to use Proof of Holdings

You need verification AND authentication for phone, email, domain, wallet, or social accounts
You want cryptographic proof of every verification, shareable and offline-verifiable
You operate internationally where SMS delivery is unreliable
You need human-in-the-loop approvals for AI agents or automation
You want to prove asset control without collecting identity documents
You need a combination of verified assets (phone + email + domain) as an alternative to KYC

Frequently Asked Questions

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300 free proofs per month. No credit card required.

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Proof vs Auth0 Best Verification APIs 2026 Comparison

Proof of Holdings vs Twilio Verify

Feature Comparison

Pricing

Cost per verification

Free tier

Multi-asset cost

Monthly plans

Reliability