Akashi Notari
Proof of existence for files: anchor a SHA-256 hash on Base, look up proofs. Paid with x402.
What can you do with Akashi Notari?
- Create an on‑chain proof: Anchor your file’s SHA‑256 hash on supported networks with a single transaction.
- Keep your privacy: Hashing happens entirely in your browser. No file uploads, ever.
- Download a PDF certificate: Instantly receive a printable certificate containing the hash, timestamp, wallet, network, transaction link, and a QR code.
- Verify later, anywhere: Re‑generate the certificate at any time using just the transaction hash or block explorer URL.
- Multi‑network support: Use Base, Ethereum Mainnet, or Optimism (more coming soon).
- Wallets you already use: Connect via MetaMask or WalletConnect-compatible wallets.
Install
Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).
claude mcp add --transport http akashi-notari 'https://anchor.akashi-notari.com/mcp'
{
"mcpServers": {
"akashi-notari": {
"type": "http",
"url": "https://anchor.akashi-notari.com/mcp"
}
}
}
Documentation
From the project's README on GitHub, refreshed weekly. Links open on GitHub.
Akashi Notari — Simple Proof of Existence
Verify and timestamp any file on the blockchain in about a minute. Your file never leaves your computer; only a cryptographic hash is written on‑chain. Typical cost is around $1 (network fees may vary).
Website
- App: https://akashi-notari.com/
- Certificate retrieval: https://akashi-notari.com/certificate/
What you can do
- Create an on‑chain proof: Anchor your file’s SHA‑256 hash on supported networks with a single transaction.
- Keep your privacy: Hashing happens entirely in your browser. No file uploads, ever.
- Download a PDF certificate: Instantly receive a printable certificate containing the hash, timestamp, wallet, network, transaction link, and a QR code.
- Verify later, anywhere: Re‑generate the certificate at any time using just the transaction hash or block explorer URL.
- Multi‑network support: Use Base, Ethereum Mainnet, or Optimism (more coming soon).
- Wallets you already use: Connect via MetaMask or WalletConnect-compatible wallets.
How it works (at a glance)
- Select a file. The site computes a SHA‑256 hash locally with a visible progress bar.
- Connect your wallet. The app shows the current network and an estimated fee in the chain’s native token.
- Click “Verify on chain.” The transaction writes the hash to the
VerifierRegistrysmart contract. - Download your PDF certificate. It includes a QR and direct link to the transaction/event log for future verification.
Certificate details
Each certificate includes:
- Filename (with safe normalization)
- SHA‑256 hash (FIPS 180‑4, 64 hex chars)
- Your wallet address
- Precise timestamp (UTC + Unix)
- Network name
- Transaction hash and a link to the explorer
- QR code linking to the transaction event log
- Simple instructions for independently recomputing and comparing the file hash in the future
Look up an existing proof
Already have a transaction? Open the Certificate page at https://akashi-notari.com/certificate/ and paste a transaction hash or full explorer URL to view registration details and download the certificate again.
Supported networks
- Base (primary)
- Ethereum Mainnet
- Optimism
Contract addresses
VerifierRegistry is the contract the web app writes to, paid in the chain's native token.
- Base:
0xeed9D0f7265892e84e43d05dA464c75add199260
Explorer: https://basescan.org/address/0xeed9D0f7265892e84e43d05dA464c75add199260#code - Ethereum:
0xeed9D0f7265892e84e43d05dA464c75add199260
Explorer: https://etherscan.io/address/0xeed9D0f7265892e84e43d05dA464c75add199260#code - Optimism:
0x859Fe07D2995875319b7e65592812392B16BBADe
Explorer: https://optimistic.etherscan.io/address/0x859Fe07D2995875319b7e65592812392B16BBADe#code
VerifierRegistryUSDC is the contract for agents. It takes payment in USDC and stores the first anchor of each hash, so firstAnchor(hash) answers whether a file was notarised. Agents reach it over x402 or MCP at https://anchor.akashi-notari.com (see workers/anchor); one anchor costs 0.01 USDC. The web app does not write to it.
- Base:
0xe0C6bB0914be3E49e13fFBc389cF659871a1bCD3
Explorer: https://basescan.org/address/0xe0C6bB0914be3E49e13fFBc389cF659871a1bCD3#code
Privacy & security
- Your document never leaves your device. Only the derived hash and transaction data are recorded on‑chain.
- No accounts, no uploads, no servers storing your files.
Disclaimer
This provides a cryptographic proof of existence only. It does not assess a document’s contents or legal validity. Store your original file safely to enable future verification.
Contact
Questions or feedback? Join the community on Discord: https://discord.gg/KBc44HTzP2
Frequently asked questions
What is Akashi Notari?
Proof of existence for files: anchor a SHA-256 hash on Base, look up proofs. Paid with x402.
How do I install Akashi Notari?
It runs as a remote server. In Claude Code: claude mcp add --transport http akashi-notari 'https://anchor.akashi-notari.com/mcp'. For other clients, paste the JSON configuration from this page into their MCP settings.
Does Akashi Notari need an API key?
Its registry entry lists no required key or secret. Some features may still need an account with the service it connects to.
Is Akashi Notari open source?
Its code is public on GitHub, but the repository does not declare a standard license.
Who maintains Akashi Notari?
It is published by self-reality. AI.tn lists it but does not maintain or endorse it.
From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.