Developer APIv1

Humanize textwith one request.

The engine behind Study Solutions, as a REST API. Prepaid and pay as you go — $0.05 per 1,000 words.

No subscriptionFailed runs refundedBalance never expires

POST /v1/humanize

Live

$ curl www.studysolutions.app/api/v1/humanize \ -H "Authorization: Bearer $SS_API_KEY" \ -d '{"text": "AI has transformed…", "stream": true}'

{"type":"start","usage":{"input_words":412,"cost_usd":0.0206}}

{"type":"paragraph","index":1,"text":"Teachers spot gaps sooner…"}

{"type":"paragraph","index":0,"text":"AI has reshaped how we learn…"}

{"type":"paragraph","index":2,"text":"Students show up ready…"}

{"type":"done","latency_ms":3840,"balance_usd":9.9794}

Paragraphs

3/3

Pay as you go
Prepaid. No plan, no minimum spend.
Failures are free
Errors and timeouts refund themselves.
Streaming
Paragraphs arrive as they finish.
Multilingual
Replies in the language you send.
Never expires
Unused balance stays yours.
Traceable
A request ID on every call.

Start here

Quickstart

Create your key in the console above, export it as SS_API_KEY, and send text. The response is the humanized document plus what it cost.

curl https://www.studysolutions.app/api/v1/humanize \
  -H "Authorization: Bearer $SS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text": "Your AI-generated text goes here."}'

Let your AI agent set it up

One click copies a setup prompt with this whole reference. Paste it into Claude Code, Cursor or Codex. View as Markdown

Keys

Authentication

Send your key as a Bearer token. x-api-key: ss_live_… also works.

Header

Authorization: Bearer ss_live_…

Keys start with ss_live_ and are shown once.
We store a SHA-256 hash, never the key.
One key per account. Lost it? Regenerate it.
Regenerating is instant: the old key fails on its next request.

Call the API from your server. A key in browser or app code can be copied by anyone who loads it.

Endpoint

Humanize

POSTwww.studysolutions.app/api/v1/humanize

Rewrites AI-generated text so it reads as human-written. Formatting — headings, lists, blank lines — is kept. The reply comes back in the language you send.

Body

textstringrequired

The text to humanize. Up to 25,000 words.

modelstring

"studysolutions". Ryne AI is coming soon — until then "ryne" returns invalid_request.default "studysolutions"

streamboolean

Stream NDJSON events as paragraphs finish. See Streaming.default false

Response

idstring

Request ID. Also in the X-Request-Id header — quote it to support.

outputstring

The humanized document.

usageobject

input_words, output_words, cost_usd.

balance_usdnumber

Balance left after this request.

latency_msnumber

Time on our side, end to end.

200 OK

{
  "id": "req_8f2c1e0b9d4a4c7f8e3b2a1d0c9e8f7a",
  "object": "humanization",
  "model": "studysolutions",
  "output": "AI has reshaped how students learn…",
  "usage": {
    "input_words": 412,
    "output_words": 405,
    "cost_usd": 0.0206
  },
  "balance_usd": 9.9794,
  "latency_ms": 3840
}

Try it

live · billed to your balance

63 words · $0.00315

Humanized text appears here.

Paragraphs stream in as each one finishes.

Optional

With "stream": true the reply is application/x-ndjson — one JSON event per line, one paragraph event per paragraph of your document. Paragraphs are written in parallel, so they can arrive out of order; place each by its index. done carries the exact document.

startRequest accepted and charged. Carries id and usage.

progressHow many paragraphs the document has.

paragraphOne finished paragraph: index + text. Lines kept as they are (headings) come first; a revised paragraph is re-sent with the same index.

doneThe assembled output, usage, balance and latency.

errorThe run failed. Nothing is charged. Ends the stream.

Event stream

{"type":"start","id":"req_8f2c…","model":"studysolutions","usage":{"input_words":412,"cost_usd":0.0206}}
{"type":"progress","paragraphs":3}
{"type":"paragraph","index":1,"text":"…"}
{"type":"paragraph","index":0,"text":"…"}
{"type":"paragraph","index":2,"text":"…"}
{"type":"done","id":"req_8f2c…","output":"…","usage":{…,"output_words":405},"balance_usd":9.9794,"latency_ms":3840}

const res = await fetch("https://www.studysolutions.app/api/v1/humanize", {
  method: "POST",
  headers: { Authorization: `Bearer ${process.env.SS_API_KEY}`, "Content-Type": "application/json" },
  body: JSON.stringify({ text, stream: true }),
});

const reader = res.body.getReader();
const decoder = new TextDecoder();
const paragraphs = [];
let buffer = "";

for (;;) {
  const { done, value } = await reader.read();
  if (done) break;
  buffer += decoder.decode(value, { stream: true });
  const lines = buffer.split("\n");
  buffer = lines.pop();
  for (const line of lines) {
    if (!line) continue;
    const event = JSON.parse(line);
    if (event.type === "paragraph") paragraphs[event.index] = event.text;
    if (event.type === "done") console.log(event.output, event.usage);
    if (event.type === "error") throw new Error(event.error.message);
  }
}

Endpoint

Balance

GETwww.studysolutions.app/api/v1/balance

Your prepaid balance, and how many words it buys at the current rate.

cURL

curl https://www.studysolutions.app/api/v1/balance \
  -H "Authorization: Bearer $SS_API_KEY"

200 OK

{
  "object": "balance",
  "balance_usd": 9.9794,
  "humanize_words_available": 199588,
  "currency": "usd"
}

Endpoint

Models

GETwww.studysolutions.app/api/v1/models

Public, no key needed. Lists the models and the price.

studysolutionsdefault

Study Solutions · $0.05 / 1K words

ryneComing soon

Ryne AI · not available over the API yet

cURL

curl https://www.studysolutions.app/api/v1/models

Reference

Errors

Every error has the same shape. Branch on error.type; messages can change.

402 Payment Required

{
  "error": {
    "type": "insufficient_balance",
    "message": "Balance is too low for this request.",
    "balance_usd": 0.0012,
    "cost_usd": 0.0206
  }
}

Status	Type	When
400	invalid_request	Body is not JSON, `text` is missing or empty, a field has the wrong type, or the model is not available yet.
413	text_too_long	Over 25,000 words (or 250,000 characters) in one request.
401	invalid_api_key	Key missing, malformed, unknown or revoked.
402	insufficient_balance	Balance is below the cost of this request.
403	account_disabled	The account is suspended or deleted.
429	concurrency_limit	3 requests already in flight on this account. Retry when one finishes.
502	engine_error	The engine failed mid-run. The charge is refunded.
504	timeout	The run took longer than 280 s. The charge is refunded.
503	service_unavailable	Temporary problem on our side. Safe to retry.

Reference

Limits & billing

$0.05 / 1,000 words

Input words, charged when the request starts. Same rate as the app.

Never charged for failures

A run that errors or times out is refunded in full, automatically.

3 requests at a time

Per account. The next one gets 429 with Retry-After — retry when one finishes.

25,000 words per request

Longer documents: split on paragraph breaks and send in parts.

Balance never expires

Top up $10–$500 at a time, by card or PayPal.

Timeouts

A run gets up to 280 s. Set your client timeout to 300 s.

Response headers

X-Request-Idstring

Same as the body id.

X-Concurrency-Limitnumber

Requests allowed in flight (3).

X-Concurrency-Remainingnumber

Free slots when this request started.

Retry-Afterseconds

On 429 only.

Benchmarks

Coming soon

Pass rates for our engine against the leading humanizers on the major AI detectors — same documents, published with the method.

Humanize textTurnitin reportswith one request.

Benchmarks

Humanize textwith one request.