Detector API
Try it Out
You can test out the API without code by going to the FastAPI link with your web browser: https://ai-detect.undetectable.ai/docs
Authentication
Undetectable.AI uses API keys to allow access to the API. You can get your API key at the top of the page in our developer portal.
UD expects for the API key to be included in all API requests to the server in a request body that looks like the following:
key: YOUR API KEY GOES HERE
You must replace YOUR API KEY GOES HERE with your personal API key.
AI Detector
Threshold
This endpoint returns a "result" score from 1-100. For best accuracy, any score under 50 is considered definitely human. 50-60 is possible AI. Over 60 is definite AI. This is the most accurate result, with 99%+ accuracy. The scores for other detectors, such as Writer and Copyleaks, are approximate and not as accurate as the main "result" score.
Detect
This endpoint allows you to submit text for AI detection. At least 200 words are recommended for best accuracy.
POST https://ai-detect.undetectable.ai/detect
Example Request
curl -X 'POST' \
'https://ai-detect.undetectable.ai/detect' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \
-d '{
"text": "Citizen science involves the public participating in scientific research. This can take many forms, collecting data on local wildlife populations to analyzing astronomical images. Citizen science projects allow researchers to gather large amounts of data and engage the public in the process. By participating, individuals contribute to valuable research while gaining a deeper understanding of the scientific world around them.",
"key": "YOUR-API-KEY-GOES-HERE",
"model": "xlm_ud_detector",
"retry_count": 0
}'Here, the request input must be less than 30,000 words.
Example Response
{
"id": "77565038-9e3d-4e6a-8c80-e20785be5ee9",
"input": "Citizen science involves the public participating in scientific research. This can take many forms, collecting data on local wildlife populations to analyzing astronomical images. Citizen science projects allow researchers to gather large amounts of data and engage the public in the process. By participating, individuals contribute to valuable research while gaining a deeper understanding of the scientific world around them.",
"model": "xlm_ud_detector",
"result": null,
"result_details": null,
"status": "pending",
"retry_count": 0
}The response contains the server-assigned ID of the document. At this point the document is now enqueued for processing. You can use the /query API endpoint to query the status of the AI Detection request. The average time to complete an AI Detection check is between 2-4 seconds. It may take longer depending on word count.
Query
This endpoint accepts a document id returned by the /detect request. And returns the status of the document submission as well as the result of the AI Detection operation as handled by various third-party AI detectors.
POST https://ai-detect.undetectable.ai/query
Example Request
curl -X 'POST' \
'https://ai-detect.undetectable.ai/query' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \
-d '{
"id": "DOCUMENT-ID-GOES-HERE"
}'Example Response
{
"id": "77565038-9e3d-4e6a-8c80-e20785be5ee9",
"model": "xlm_ud_detector",
"result": 88.0,
"result_details": {
"scoreGptZero": 50.0,
"scoreOpenAI": 0.0,
"scoreWriter": 0.0,
"scoreCrossPlag": 0.0,
"scoreCopyLeaks": 50.0,
"scoreSapling": 0.0,
"scoreContentAtScale": 0.0,
"scoreZeroGPT": 50.0,
"human": 88.0
},
"status": "done",
"retry_count": 0
}Here, "result": 88.0 means that given our 50% threshold, the text is AI-generated. Similarly, "scoreZeroGPT": 50.0 signifies that the text is likely 50% human-written as per ZeroGPT. The Same goes for the rest of the other detectors.
Check User Credits
This endpoint accepts the users apikey via the header. And returns users credit details.
GET https://ai-detect.undetectable.ai/check-user-credits
Example Request
curl -X 'POST' \
'https://ai-detect.undetectable.ai/query' \
-H 'apikey: YOUR API KEY GOES HERE' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \Example Response
{
"baseCredits": 10000,
"boostCredits": 1000,
"credits": 11000
}Sentence Level AI Detection
The sentence-level AI Detector runs on top of a WebSocket-based protocol.
Here are the necessary steps needed to get sentence-level results for your text.
- Connect to the WebSocket
- Listen for all events received from the WebSocket
- Send a document_watch request
- Receive a document_id event
- Take the id generated by the document_id response and submit a document for AI Detection
- Start receiving document_chunk events. document_chunk events will return each sentence together with the sentence-level result
- When the document finishes processing, you will receive a document_done event.
This section will describe the necessary steps to connect, send a document for processing, and listen to the sentence stream until it finishes.
Connect to the WebSocket
This endpoint allows you to establish the WebSocket connection
POST https://ai-detect.undetectable.ai/ws/$USER_ID
Example code:
ws = new WebSocket("wss://https://ai-detect.undetectable.ai/ws/1722238709737x2194626580942121212");Listen for all events received from the WebSocket
Once the WebSocket connection is established, listen to events sent through the WebSocket connection.
Example code:
ws.addEventListener("message", (event) => {
console.log("Message from server ", event.data);
});Send a document_watch request
Send interest in sending a document by sending a document_watch request on the WebSocket
Example code:
ws.send(JSON.stringify({
"event_type": "document_watch",
"api_key": "$API_KEY",
}))Receive a document_id event
After sending a document_watch event, the server returns a document_id event.
Example response:
{
"event_type": "document_id",
"success": true,
"document_id": "512da191-166926922-44cb-81c6-191ae3a807aa"
}Submit an AI Detection Request
Take the id generated by the document_id response and submit a document for AI Detection
POST https://ai-detect.undetectable.ai/detect
Example Request
curl -X 'POST' \
'https://ai-detect.undetectable.ai/detect' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \
-d '{
"text": "Citizen science involves the public participating in scientific research. This can take many forms, collecting data on local wildlife populations to analyzing astronomical images. Citizen science projects allow researchers to gather large amounts of data and engage the public in the process. By participating, individuals contribute to valuable research while gaining a deeper understanding of the scientific world around them.",
"key": "YOUR-API-KEY-GOES-HERE",
"model": "xIm_ud_detector",
"id": "512da191-166926922-44cb-81c6-191ae3a807aa"
}'Example Response
{
"id": "512da191-166926922-44cb-81c6-191ae3a807aa",
"input": "Citizen science involves the public participating in scientific research. This can take many forms, collecting data on local wildlife populations to analyzing astronomical images. Citizen science projects allow researchers to gather large amounts of data and engage the public in the process. By participating, individuals contribute to valuable research while gaining a deeper understanding of the scientific world around them.",
"model": "xIm_ud_detector",
"result": null,
"result_details": null,
"status": "pending",
"retry_count": 0
}Receive sentence level results
Start receiving document_chunk events. document_chunk events will return each sentence together with the sentence level result
Example responses:
{
"event_type": "document_chunk",
"document_id": "512da191-166926922-44cb-81c6-191ae3a807aa"
"model": "xIm_ud_detector",
"chunk": "Citizen science involves the public in scientific research.",
"result": 0.714
}When the document finishes processing, you will receive a document_done event.
Example responses:
{
"event_type": "document_done",
"document_id": "512da191-166926922-44cb-81c6-191ae3a807aa"
"model": "xIm_ud_detector"
}Below is an example sequence as returned by the WS stream.
Handling exceptional circumstances
If for some reason the server encounters an error while doing the humanization, a document_error event will be sent to the websocket client. The client should act as appropriate, for example a UI will show an error message.
For example, the server will send a REQUEST_TIMEOUT error code when it takes more than 20 seconds across chunk events.
{
"event_type": "document_error",
"document_id": "512da191-166926922-44cb-81c6-191ae3a807aa"
"error_code": "REQUEST_TIMEOUT",
"message": "Request timeout. Took 20 seconds.",
}Cancellations
There will be instances when the UI would want to cancel the operation. The user decides to close the window, or cancels the event explicitly
When this happens you should sent a document_halt event
Example responses:
{
"event_type": "document_halt",
"document_id": "512da191-166926922-44cb-81c6-191ae3a807aa"
}Errors
Most errors will be from incorrect parameters being sent to the API. Double check the parameters of each API call to make sure it's properly formatted, and try running the provided example code.
The generic error codes we use conform to the REST standard:
| Error Code | Meaning |
|---|---|
| 400 | Bad Request -- Your request is invalid. |
| 403 | Forbidden -- The API key is invalid, or there aren't sufficient credits (0.1 per word). |
| 404 | Not Found -- The specified resource doesn't exist. |
| 405 | Method Not Allowed -- You tried to access a resource with an invalid method. |
| 406 | Not Acceptable -- You requested a format that isn't JSON. |
| 410 | Gone -- The resource at this endpoint has been removed. |
| 422 | Invalid Request Body -- Your request body is formatted incorrectly or invalid or has missing parameters. |
| 429 | Too Many Requests -- You're sending too many requests! Slow it down! |
| 500 | Internal Server Error -- We had a problem with our server. Try again later. |
| 503 | Service Unavailable -- We're temporarily offline for maintenance. Please try again later. |
Common Issues and Solutions
Authentication Issues
"User verification failed" (403)
- Cause: Invalid or expired API key
- Solution:
Verify your API key is correct
Check if your API key is active in your account
Try regenerating your API key
"Not enough credits" (403)
- Cause: Insufficient credits for text processing
- Solution:
Check your remaining credits using /check-user-credits
Purchase additional credits if needed
Use shorter text inputs to consume fewer credits
Input Validation Issues
"Input text cannot be empty" (400)
- Cause: Empty or whitespace-only text submitted
- Solution:
Ensure your text input is not empty
Remove any leading/trailing whitespace
Check if text encoding is correct
"Input email is empty" (400)
- Cause: Missing email for URL processing
- Solution:
Provide a valid email address when submitting URLs
Check email format is correct
Processing Issues
"Request timeout" (WebSocket)
- Cause: Document processing took too long (>120 seconds)
- Solution:
Try with a smaller text input
Check if the service is experiencing high load
Retry the request
Document Status "failed"
- Cause: Processing failed for various reasons
- Solution:
Check if input text meets minimum requirements
Verify text is in a supported format
Try with a different model
Contact support if issue persists
WebSocket Connection Issues
Connection Drops
- Cause: Network issues or server disconnects
- Solution:
Check your network connection
Implement reconnection logic
Verify WebSocket URL is correct
"User not found" (WebSocket)
- Cause: Invalid user ID in WebSocket connection
- Solution:
Verify user ID is correct
Ensure user account is active
Re-authenticate if needed
Updated on: 03/04/2025
Thank you!