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8k4 Protocol — Create Signed Metadata Upload Nonce
x402
8k4 Protocol — Create Signed Metadata Upload Nonce is a paid API for AI agents from api.8k4protocol.com, paid per call via x402, $0.001/call, status down (last checked 2026-09-15).
Generates a signed nonce required to authorize an ERC-8004 agent metadata upload
Price / call$0.001
Success—
StatusDown
How this service works
Create a signed metadata upload nonce
Output
A signed nonce value that must be included when calling the ERC-8004 metadata upload endpoint, serving as a one-time authorization token to prevent replay attacks and authenticate the upload request.
Example use cases
Example prompt
“I need to upload signed metadata for my ERC-8004 agent — can you get me a fresh signed upload nonce from the 8k4 Trust API so I can proceed with the metadata submission?”
Technical details
Endpoint
POSThttps://api.8k4protocol.com/metadata/nonceWhen to prefer
Use this endpoint as the mandatory first step before uploading signed ERC-8004 metadata. This nonce is required by the 8k4 Protocol's upload endpoint to ensure authenticity and prevent replay attacks. Choose this when your agent needs to publish or update its trust metadata on-chain via the 8k4 Protocol.
Side effects
- Invalid or malformed properties payload returns a 400 error
- Missing required properties field causes schema validation failure
- Expired nonce if too much time passes before using it in the upload step
- Rate limiting or insufficient USDC balance causes payment failure via x402
- Network timeout or service unavailability returns 5xx error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| properties | string |
Tags
x402
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