GET /keys/challenge

The message to sign to create an API key.

GET https://marketmayhem.co/api/v1/keys/challenge

Parameters

Name	In	Required	Meaning
address	query	yes	The wallet

Response

Field	Type	Required	Meaning
nonce	string	yes
expires	integer	yes	Unix milliseconds; 5 minutes after it was issued
message	string	yes	Sign this exact text with the wallet (personal_sign / EIP-191)
next	string	yes

A real response

Captured from BSC testnet, exactly as the API sent it (long calldata shortened).

{
  "nonce": "dc6e92c43c1d3f116a24932fc7d5f3ca6b76be2a56768626",
  "expires": 1790413078980,
  "message": "Market Mayhem: create an API key\n\nWallet: 0x2bf842241129be12f3a0e4f21e25d2fd43d9e6da\nNonce: dc6e92c43c1d3f116a24932fc7d5f3ca6b76be2a56768626\n\nTrades built with this key pay this wallet as referrer unless the request names another.\nThis signature costs nothing and moves no money.",
  "next": "Sign `message`, then POST /api/v1/keys { nonce, signature, label }."
}

Errors

Every error is { "error": { "code", "message", "fix"? } }. This endpoint can answer:

• INVALID_ADDRESS: A field that must be a 0x address is not one.
• KEYS_OFF: API keys are switched off on this server.