Sigil Mail is a real email provider where your XPR Network wallet is your login — no password, no captcha. Humans verify once with in-app KYC and get a 250 MB mailbox. AI agents link to a KYC'd human wallet via agentcore and get their own independent mailbox.
Features
Built on open standards — JMAP, IMAP, SMTP — with a wallet-signature auth layer on top. No vendor lock-in, no passwords to leak.
Your XPR Network wallet is your identity. Sign a challenge with your key — no password, no recovery email, no 2FA codes. One tap in WebAuth and you're in.
Agents hold their own private key and sign programmatically — no wallet popups. An agent must be linked to its human owner via agentcore to create a mailbox. After that, it reads, sends, and manages email fully autonomously.
Account creation requests live on-chain via the mailsigil contract. Humans approve with a wallet signature — trustless, auditable, no server can fake consent.
Full JMAP, IMAP, and SMTP — compatible with every email client, every automation tool. Real deliverable email at mailsigil.pro, ready the moment you KYC and sign in.
Grant an AI agent access to your inbox — scoped to read, send, or full access. Revoke instantly. No key exchange, no shared passwords. Pure cryptographic delegation.
Access your own inbox and your agent's inbox in the same webmail session. One click to switch — see what your agent is sending and receiving on your behalf, in real time.
Every mailbox requires KYC. New humans verify once in the WebAuth app and get the full 250 MB. AI agents cannot create a mailbox on their own — they must be agentcore-linked to a KYC'd human (or hold an invite code) and inherit that tier. Each human sponsors one agent mailbox free; extras are a $1 on-chain upgrade. Spam-resistant by design, not by policy.
How it works
Works for humans, AI agents, or both together. The same four steps regardless of who is doing them.
Create a free XPR Network account at webauth.com — biometric signup, takes 30 seconds — then complete the in-app KYC. AI agents use npx create-xpr-agent to generate their own account and key.
Humans: complete KYC inside WebAuth, then open Sigil Mail and tap "Sign in with XPR Wallet" — one tap and you're in. Agents: register in agentcore and link to a human wallet first, then sign programmatically with your private key.
yourname@mailsigil.pro is auto-provisioned the first time you sign in. Full IMAP/SMTP/JMAP access, compatible with any email client or AI tool.
Register your agent in the XPR agentcore registry and link it to your wallet. Grant it access to your inbox — scoped and revocable. Your agent now manages email for you.
XPR Network
XPR Network is a zero-gas, 0.5-second block chain purpose-built for AI agents and human-grade UX. Sigil uses it as the trust and identity layer.
Official on-chain agent-to-human linking. Agents must be registered and linked to create a Sigil mailbox — one agent per human wallet on the free tier. KYC trust and storage quota flow down from the human owner.
When an agent requests a mailbox for you, you receive a confirmation link via chat. Open it, sign with your wallet, and the mailbox is live. SMS and email delivery coming soon.
XPR Network runs on staked resources, not per-transaction fees. Using Sigil costs you nothing in gas — ever.
For AI Agents
Sigil is designed so AI agents can manage email autonomously — no human babysitting required. Every interface is machine-readable.
Agents authenticate by signing a digest with their private key — stateless, no wallet popup, no human in the loop. Standard XPR A2A signature scheme.
JMAP is JSON-native and designed for programmatic access. Read threads, search, send, archive — all in clean JSON. No MIME parsing, no POP3 quirks.
6 JMAP tools + 10 grant management tools available as an MCP server. Drop it into any MCP-compatible agent framework and your agent has a full inbox.
Owners grant agents read, send, or full access. Scope is enforced at the tool layer. Revoke anytime — the agent's credential is invalidated immediately.
A plain-text guide at /llms.txt teaches any LLM the full Sigil API surface, auth flows, and smart contract integration. Optimized for context windows.
Agents cannot provision a mailbox for a human without on-chain approval. The human signs. The chain records it. No server override is possible.
Get started
No signup form. No credit card. Verify once with KYC in WebAuth, then sign in with your XPR wallet.