API documentation

With the Do4U API you use the same tools as on the website from your own software: summarise, compare, support replies, alt texts, rewrite and translate. Every request is processed on our own servers in Poland, EU.

Base URL: https://do4u.eu/api/v1

OpenAPI 3.1 description (JSON) – Machine-readable description of this API for code generators and tools such as Postman or Insomnia. No key needed.

Authentication

Create a key under API keys in your account. Send it with every request in the header Authorization: Bearer <key> (or X-API-Key: <key>). Keep the key secret and never put it into a web page. You can revoke a key at any time.

How it works

Jobs run asynchronously. You create a job and get its id at once (HTTP 202). Then you fetch the job until its status is done or failed. Ask every 2 to 5 seconds; most jobs take a few seconds.

Endpoints

Example

Create a job, then fetch the result:

curl -X POST https://do4u.eu/api/v1/jobs \
  -H "Authorization: Bearer d4u_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"tool": "summarize", "text": "...", "options": {"length": "short"}, "language": "en"}'

HTTP/1.1 202 Accepted
{"id": "8f1c0b6a...", "tool": "summarize", "status": "queued", "model": "do4u-standard",
 "credits_estimate": 1, "links": {"self": "https://do4u.eu/api/v1/jobs/8f1c0b6a..."}}

curl https://do4u.eu/api/v1/jobs/8f1c0b6a... -H "Authorization: Bearer d4u_YOUR_KEY"

{"id": "8f1c0b6a...", "tool": "summarize", "status": "done", "model": "do4u-standard", "credits_estimate": 1,
 "result": {"summary": "...", "key_points": ["...", "..."]}, "credits": 1,
 "notice": "AI-generated, please check before use."}

curl -X POST https://do4u.eu/api/v1/jobs -H "Authorization: Bearer d4u_YOUR_KEY" \
  -F tool=alt_text -F language=de -F "text=Product page: hiking boots" -F image=@photo.jpg

Request fields for POST /jobs

Repeat requests safely (Idempotency-Key)

Send the header Idempotency-Key with POST /jobs, for example a random UUID for each job (1 to 255 printable ASCII characters). If the connection breaks and you send the same request again with the same Idempotency-Key and the same API key within 24 hours, you get the same answer again: the same job, no second job and no second charge. The answer then has the header Idempotent-Replayed: true. Use a new key for every new job. If you send the same key with a different request, you get 422 idempotency_conflict. Errors are not stored: after an error you can send the request again with the same key.

curl -X POST https://do4u.eu/api/v1/jobs \
  -H "Authorization: Bearer d4u_YOUR_KEY" \
  -H "Idempotency-Key: 5f0c2a8e-7d1b-4c3a-9e2f-1b6d8a4c0e77" \
  -H "Content-Type: application/json" \
  -d '{"tool": "summarize", "text": "..."}'

Tools and options

Job status

queued and running: still working (position and wait_seconds help you to wait). done: result contains the fields of the tool. failed: nothing was charged (credits is 0); error.code names the reason: address_blocked (Do4U does not open this address, for example a private or internal one; send the text or HTML instead), input_too_large (shorten the input), image_unavailable or job_failed. expired: the result is no longer stored.

Webhookovi

Dodaj "callback_url" u POST /api/v1/jobs i Do4U šalje potpisani POST (događaj job.finished sa statusom, kreditima i poveznicom na rezultat - ne sam rezultat) čim je zadatak gotov. Samo javne adrese na portu 80 ili 443; ponavljamo do 6 puta s rastućim razmacima.

Primjer: izradi zadatak s callback_url – i zahtjev koji Do4U šalje na tu adresu kad je zadatak gotov:

curl -X POST https://do4u.eu/api/v1/jobs \
  -H "Authorization: Bearer d4u_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"tool": "summarize", "text": "...", "callback_url": "https://example.com/do4u-hook"}'

POST /do4u-hook
Content-Type: application/json
X-Do4U-Event: job.finished
X-Do4U-Signature: t=1793180000,v1=6b1f...

{"event":"job.finished","id":"8f1c0b6a...","tool":"summarize","status":"done","credits":1,
 "created":"2026-10-28T10:00:00+01:00","finished":"2026-10-28T10:00:04+01:00","result_url":"https://do4u.eu/api/v1/jobs/8f1c0b6a..."}

Provjeri zaglavlje X-Do4U-Signature: t=<time>,v1=<hex>, gdje je v1 = HMAC-SHA256(secret, "<time>.<raw body>"). Odbaci stara vremena (npr. starija od 5 minuta). Tvoja tajna počinje s whsec_ i prikazuje se na stranici API ključevi.

// Node.js: rawBody = the request body exactly as received (string)
const crypto = require('crypto');
function do4uSignatureOk(rawBody, header, secret) {
  const t = (header.match(/t=(\d+)/) || [])[1];
  const v1 = (header.match(/v1=([0-9a-f]{64})/) || [])[1];
  if (!t || !v1 || Math.abs(Date.now() / 1000 - Number(t)) > 300) return false;
  const expected = crypto.createHmac('sha256', secret).update(t + '.' + rawBody).digest('hex');
  return crypto.timingSafeEqual(Buffer.from(expected), Buffer.from(v1));
}

// PHP
function do4u_signature_ok(string $raw, string $header, string $secret): bool {
    if (!preg_match('/t=(\d+),v1=([0-9a-f]{64})/', $header, $m) || abs(time() - (int)$m[1]) > 300) return false;
    return hash_equals(hash_hmac('sha256', $m[1] . '.' . $raw, $secret), $m[2]);
}
$ok = do4u_signature_ok(file_get_contents('php://input'), $_SERVER['HTTP_X_DO4U_SIGNATURE'] ?? '', 'whsec_YOUR_SECRET');

credits.low

Kad stanje kredita računa padne ispod praga, Do4U šalje jedan potpisani POST na adresu webhooka računa. Događaj ne sadrži osobne podatke, samo stanje, prag i vrijeme (UTC). Sljedeći slijedi tek nakon što se krediti ponovno dodaju (kupnja, mjesečni besplatni krediti ili vaučer). Potpis i tajni ključ isti su kao za job.finished.

POST /do4u-hook
Content-Type: application/json
X-Do4U-Event: credits.low
X-Do4U-Signature: t=1793180000,v1=6b1f...

{"event":"credits.low","balance":18,"threshold":20,"ts":"2026-10-29T10:00:04Z"}

Adresu i prag postavljaš ovdje: API ključevi

n8n

Gotov tijek rada: webhook prima poziv od Do4U-a, provjerava potpis, dohvaća rezultat i predaje ga tvom sljedećem koraku.

Preuzmi n8n predložak (JSON)

Predložak, još nije testiran u stvarnoj n8n ili Make instanci – testiraj provjeru potpisa prije upotrebe.

U n8n-u: Workflows → Import from file. Zatim unesi svoju tajnu u čvor "Check signature" i svoj API ključ u "Do4U: get result", aktiviraj tijek rada i koristi produkcijski URL webhooka kao callback_url. Samostalno hostirani n8n za provjeru potpisa treba varijablu okruženja NODE_FUNCTION_ALLOW_BUILTIN=crypto.

Make

1. Dodaj modul Webhooks → Custom webhook kao okidač i u njegovim naprednim postavkama uključi "JSON pass-through" i "Get request headers".
2. Koristi adresu ovog webhooka kao callback_url.
3. Provjeri potpis: usporedi v1 iz zaglavlja X-Do4U-Signature s sha256(t + "." + raw body; hex; tvoja tajna).
4. Dodaj HTTP → Make a request: GET na result_url sa zaglavljem Authorization: Bearer <your API key>.
5. Koristi polje result u svojim sljedećim modulima.

Predložak, još nije testiran u stvarnoj n8n ili Make instanci – testiraj provjeru potpisa prije upotrebe.

Recepti: povezani alati

Recept izvršava 2 do 4 alata jedan za drugim kao jedan posao. Pošalji "recipe" umjesto "tool": ili naziv gotovog recepta ili popis koraka. Tekst ulazi u prvi korak; rezultat svakog koraka je tekst za sljedeći korak. GET /api/v1/recipes navodi gotove recepte, alate koje možeš koristiti i polje koje svaki alat prosljeđuje dalje.

curl -X POST https://do4u.eu/api/v1/jobs \
  -H "Authorization: Bearer d4u_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"recipe": [{"tool": "summarize", "options": {"length": "short"}},
               {"tool": "translate", "options": {"target": "pl"}}], "text": "..."}'

curl -X POST https://do4u.eu/api/v1/jobs \
  -H "Authorization: Bearer d4u_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"recipe": "summary_translate_meta", "options": {"target": "pl"}, "text": "..."}'

Dobivaš jednu procjenu za sve korake (credits_estimate). Taj iznos se rezervira na početku. Nakon svakog koraka knjiži se stvarna potrošnja, a ostatak ostaje rezerviran do kraja, kada se oslobađa. Neuspjeli korak ne košta ništa, preostali koraci se preskaču, a koraci koji su već završeni naplaćuju se.

HTTP/1.1 202 Accepted
{"id": "3c9e0d1a...", "tool": "recipe", "recipe": null, "status": "queued", "model": "do4u-standard", "credits_estimate": 4,
 "steps": [{"n": 1, "tool": "summarize", "credits_estimate": 2}, {"n": 2, "tool": "translate", "credits_estimate": 2}],
 "links": {"self": "https://do4u.eu/api/v1/jobs/3c9e0d1a..."}}

GET /api/v1/jobs/{id} prikazuje svaki korak sa statusom (pending, queued, running, done, failed, skipped), njegovim credits, obavijesti input_shortened ako je tekst morao biti skraćen za sljedeći alat te rezultat svakog koraka kada se recept završi. S no_store rezultati se prikazuju jednom. callback_url se aktivira jednom, na kraju recepta.

GET https://do4u.eu/api/v1/jobs/3c9e0d1a...

{"id": "3c9e0d1a...", "tool": "recipe", "status": "done", "credits_estimate": 4, "credits": 3, "steps_total": 2,
 "steps": [{"n": 1, "tool": "summarize", "status": "done", "credits": 1, "result": {"summary": "...", "key_points": ["..."]}},
           {"n": 2, "tool": "translate", "status": "done", "credits": 2, "notices": ["input_shortened"], "result": {"translation": "...", "notes": []}}],
 "result": {"translation": "...", "notes": []}}

GET https://do4u.eu/api/v1/recipes

Errors

Errors always have the same form: {"error": {"code": "...", "message": "..."}}. With 429 and 503 the header Retry-After says how many seconds to wait.

Limits

• 60 requests per minute per key and 120 per account.
• Open jobs at the same time per account: Free 3, Starter 3, Standard 5, Pro 10, for the website and the API together.
• Input: Free 8 000 characters, paid packages 30 000. Lower limits per tool: compare 20 000, alt_text 1 000, translate 12 000 (compare: both texts together).
• API keys: Free 1, Starter 1, Standard 5, Pro 10.

Credits

A new job shows an estimate (credits_estimate); charged is the actual use (credits). Failed jobs cost nothing. Free credits are used first.

Data

Inputs and results are stored for 7 days (Free) or 30 days (paid packages), then deleted. Images are deleted right after processing. Results are AI-generated: please check them before you use them.

Odgovaraj na e-poruke bez promjene sandučića

Do4U ne vodi sandučić i nikad ne pohranjuje podatke za pristup tvom poštanskom sandučiću. Dva načina da ipak dobiješ nacrte odgovora:

S1 – Predložak za n8n ili Make

1. Okidač: nova e-poruka u tvom sandučiću (IMAP okidač u n8n-u ili Makeu – podaci za pristup ostaju tamo)
2. POST /api/v1/jobs s alatom support_reply, tekstom e-poruke i no_store: true
3. Pričekaj nekoliko sekundi i dohvaćaj GET /api/v1/jobs/{id} dok status ne bude done
4. Izradi nacrt u svom sandučiću s tekstom iz result.reply (modul Gmail ili Outlook)

Preuzmi n8n predložak (JSON)

U Makeu izgradi isti scenarij od modula Email (watch emails), HTTP (make a request), Sleep i Gmail ili Outlook (create a draft).

Razvojna proširenja i dodaci za trgovine

Raspakiraj ZIP i pročitaj priloženi vodič. Proširenje za preglednik učitaj lokalno; dodatke za trgovine prvo provjeri u probnoj trgovini. Potreban je tvoj vlastiti Dev API ključ. Shopware trenutačno nudi CLI.

• Do4U za WordPress (ZIP)
• Chrome / Firefox · Dev (ZIP)
• WooCommerce · Dev (ZIP)
• Shopware · CLI · Dev (ZIP)