Proof of existence for files: anchor a SHA-256 hash on Base, look up proofs. Paid with x402.
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Paid with x402 (USDC on Base). Writes the SHA-256 hash of a file on-chain; the block time becomes the proof of existence. Compute the hash locally and never send the file. The hash, the filename and the payer address become public and permanent. Without a payment in _meta["x402/payment"] the result is the payment requirement.
SHA-256 of the file, 64 hex characters
Optional name to record with the hash: a-z 0-9 - _ .
This tool isn't marked read-only, so it may change something on the server or in an account you connected.
Paid with x402 (USDC on Base). Writes the SHA-256 hash of a file on-chain; the block time becomes the proof of existence. Compute the hash locally and never send the file. The hash, the filename and the payer address become public and permanent. Without a payment in _meta["x402/payment"] the result is the payment requirement.
| Argument | Type | Description |
|---|
| hash* | string | SHA-256 of the file, 64 hex characters |
| filename | string | Optional name to record with the hash: a-z 0-9 - _ . |
{
"type": "object",
"required": [
"hash"
],
"properties": {
"hash": {
"type": "string",
"pattern": "^(0x)?[0-9a-fA-F]{64}$",
"description": "SHA-256 of the file, 64 hex characters"
},
"filename": {
"type": "string",
"maxLength": 128,
"description": "Optional name to record with the hash: a-z 0-9 - _ ."
}
}
}Free. Look up whether a file hash is anchored on Base and when, or read the proof written by a transaction. Pass `hash` or `tx`. Call it before anchor_hash to avoid paying for a hash that is already anchored.
| Argument | Type | Description |
|---|---|---|
| tx | string | Transaction hash; use instead of hash |
| hash | string | SHA-256 of the file, 64 hex characters |
{
"type": "object",
"properties": {
"tx": {
"type": "string",
"pattern": "^0x[0-9a-fA-F]{64}$",
"description": "Transaction hash; use instead of hash"
},
"hash": {
"type": "string",
"pattern": "^(0x)?[0-9a-fA-F]{64}$",
"description": "SHA-256 of the file, 64 hex characters"
}
}
}