funsolver

Documentation

API reference and integration guide

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Castle

Price per 1000 successful solves:$3.00 / 1k

task parameters

HTTP
POST https://api.funsolver.com/createTask
Content-Type: application/json

{
  "clientKey": "fsk_abc...",
  "task": {
    "type": "CastleTask",
    "websiteURL": "https://example.com/protected-page",
    "proxy":      "http://user:pass@host:port",
    "cookies": [
      { "name": "session", "value": "...", "domain": ".example.com", "path": "/" }
    ]
  }
}
type
stringrequired
"CastleTask"
websiteURL
stringrequired
URL of the Castle-protected page. Its domain must be on the allow-list.
proxy
stringrequired
Proxy as http://user:pass@host:port. Supported schemes: http, https, socks5. Solves run under the client's proxy only — no server-side proxy pool.
cookies
array
Optional cookies as { name, value, domain, path } objects — loaded into the session before solving.

getTaskResult response

JSON
{
  "errorId": 0,
  "status": "ready",
  "solution": {
    "token":           "...",
    "userAgent":       "Mozilla/5.0 (Windows NT 10.0; Win64; x64) ... Chrome/149.0.0.0 ...",
    "acceptLang":      "en-US,en;q=0.9",
    "secChUa":         "\"Chromium\";v=\"149\", \"Google Chrome\";v=\"149\", \"Not_A Brand\";v=\"99\"",
    "secChUaPlatform": "\"Windows\"",
    "cookies":         { "name": "value" }
  },
  "processingTime": 5.4
}

On the next request to the Castle-protected API replay ALL 5 header fields verbatim alongside the token and cookies — UA / sec-ch-ua mismatch causes Castle to invalidate the token immediately.

Allowed domains

No domains configured yet. Open a support ticket to request one.

Spotted an error? Tell support.
For AI agents: machine-readable reference — /llms.txt