AI Detector API
Identify AI-generated text with sentence-level probability scoring and confidence insights.
Enterprise-grade uptimeThe authenticity layer for the AI content era.
One API to detect, humanize, and verify AI content across production writing workflows.
PRODUCT
curl -X POST https://developer-portal.walterwrites.ai/api/detector/
-H "Content-Type: application/json"
-H "X-API-Key: YOUR_API_KEY"
-d '{
"content": "Artificial intelligence has transformed many industries."
}'"status": "success",
"result": "ai",
"ai_score": 0.87,
"items": [{ "prediction": "ai-generated", "ai_score": 0.87 }],
"word_count": 7,
"credits_remaining": 1993curl -X POST https://developer-portal.walterwrites.ai/api/humanizer/
-H "Content-Type: application/json"
-H "X-API-Key: YOUR_API_KEY"
-d '{
"content": "Artificial intelligence has transformed many industries."
}'"status": "success",
"task_id": null,
"result": "AI has changed many industries.",
"execution_time": 2.34,
"word_count": 7,
"credits_remaining": 1993curl -X POST https://developer-portal.walterwrites.ai/api/plagiarism/scan/
-H "Content-Type: application/json"
-H "X-API-Key: YOUR_API_KEY"
-d '{
"content": "Text of at least 50 characters to scan against web sources."
}'"status": "success",
"plagiarism_score": 0.12,
"verdict": "minor_similarity",
"sources": [{ "url": "https://example.com/source" }],
"highlights": [{ "start": 0, "end": 24, "source_index": 0 }],
"credits_remaining": 1998curl -X POST https://developer-portal.walterwrites.ai/api/image-detector/predict/
-H "X-API-Key: YOUR_API_KEY"
-F "[email protected];type=image/jpeg""prediction": "real",
"confidence": 0.9964,
"probabilities": {
"real": 0.9964,
"fake": 0.0013,
"inpainting": 0.0022
"credits_charged": 6curl -X POST https://developer-portal.walterwrites.ai/api/grammar/correct/
-H "Content-Type: application/json"
-H "X-API-Key: YOUR_API_KEY"
-d '{
"content": "This are a sample sentence with grammar mistake."
}'"status": "success",
"corrected_text": "This is a sample sentence with grammar mistakes.",
"diff": [{ "type": "replace", "original": "are", "corrected": "is" }],
"edits_count": 2,
"changed": true,
"input_words": 8Five APIs. One integration.
Use one developer portal and scoped API keys for humanization, text detection, image detection, grammar correction, and plagiarism scanning.
AI Humanizer API
Refine AI-generated text into natural, human-sounding output that reads authentically.
Plagiarism Checker API
Scan text against web sources and return scores, matched URLs, and highlighted ranges.
Grammar Checker API
Correct grammar, spelling, and punctuation and return a complete word-level diff.
AI Image Detector API
Upload an image and receive a real, fake, or inpainting verdict with per-class probabilities.
Start free. One credit pool, every API.
Every endpoint draws from a single monthly credit balance. Start on the free tier, then pick the plan that fits your volume.
Need enterprise pricing?
Talk to us about higher-volume workloads and enterprise deployment requirements.
Built for documented production workflows.
Use scoped keys, predictable JSON responses, safe retry controls, and synchronous or asynchronous processing where supported.
Scoped API keys
Grant only the Humanizer, AI Detector, Image Detector, Grammar Checker, or Plagiarism Checker scopes each key needs.
Learn more
Sync and async processing
Humanizer and AI Detector support synchronous responses, webhooks, polling, or both.
Learn more
Safe retries
Grammar and plagiarism endpoints accept idempotency keys to prevent duplicate charges during retries.
Learn more
Usage visibility
Responses return word counts, credits, execution details, or exact image credit charges as documented.
Learn more
Documented errors
Use the published status codes and error codes to handle invalid input, insufficient credits, conflicts, and temporary service failures.
Learn moreWhat you can build with Walter.
Teams use Walter APIs to verify, refine, and protect content at every stage of the workflow.
Content moderation
Review text and image submissions with the documented Detector and Image Detector responses before routing content for human review.
Academic integrity
Combine AI probability signals, sentence details, source matches, and highlighted ranges in a reviewer-led workflow.
Editorial review
Add humanization, grammar correction, and plagiarism scanning to editing and approval steps.
Synthetic media detection
Classify uploaded images as real, fake, or inpainting and retain the returned probabilities for review.
AI-assisted writing
Use the Humanizer and Grammar Checker endpoints to help users revise and polish drafts in your product.
Publishing and research
Return source-match evidence and text corrections before content moves into publication.
Frequently asked questions.
Documented answers about authentication, endpoints, credits, and response handling.
What can I do with the Walter API?
Walter provides documented endpoints for humanization, AI text detection, AI image detection, grammar correction, plagiarism scanning, and a combined detect-and-humanize workflow.
How do I authenticate?
Create an API key in the developer portal, select the scopes it needs, and send the key in the X-API-Key header. The full key is shown once when it is created.
How are credits calculated?
Most text endpoints use 1 credit per word. Grammar correction uses 1 credit per script-aware word, plagiarism scans cost 2 credits per scan, and image detection is priced by image resolution.
Which endpoints support asynchronous processing?
Humanizer and AI Detector support synchronous processing, webhooks, polling, or both. Grammar and plagiarism requests are synchronous.
How should detector scores be used?
Treat AI and source-similarity scores as review signals, not final verdicts. Evaluate the returned sentence details, sources, and context before making a decision.
Where are the request fields and errors documented?
The Walter developer documentation lists each endpoint, required scope, request fields, limits, response schema, credit rules, and error codes.
Get an API key.
Create a key in the developer portal, select the scopes your integration needs, and store the full key when it is shown.
Read the docs.
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