Proof of Work Verification

The /pow endpoint verifies a solved proof-of-work challenge: send back the token issued with the challenge, along with the nonce you found.

Parameters

The request body must be JSON:

Parameter	Required	Description
`token`	Yes	Token issued by the challenge
`nonce`	Yes	Nonce found by the client

Field	Type	Description
`valid`	`boolean`	`true` if the proof is accepted
`reason`	`string`	Why it was rejected — absent when `valid` is `true`

Reason	Meaning
`wrong`	The nonce does not produce a digest with enough leading zeros
`expired`	The token is older than 5 minutes
`used`	The token was already redeemed — each one works exactly once
`invalid`	The token is malformed or not a proof-of-work token

curl -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "token": "eyJ...",
    "nonce": "48123"
  }' \
  "https://api.sylvain.sh/v5/pow"

token*

nonce*

If parameters are missing or invalid, the API will return an error:

Error Message	Description
`Please provide a token (?token={token})`	The `token` is missing
`Please provide a nonce (&nonce={nonce})`	The `nonce` is missing