GPTZero | EmpirioLabs AI Docs

GPTZero · Tools & Agents

POST /v1/detect

Deep-learning detector that flags portions of text likely generated by AI versus human, classifying content as entirely human, AI, or mixed.

At a glance

Field	Value
Model id	`gptzero`
Input modalities	Text, Document
Output modalities	Text
Context window	-
Weight precision	-
Features	ai_detection, classification
Native inference	No
New	No
Supported endpoints	`POST /v1/detect`, `POST /v1/chat/completions`, `POST /v1/responses`, `POST /v1/messages`

Pricing

Charge	Spec	Rate
Text Scan	per 1,000 words	$0.39

Example request

$ curl https://api.empiriolabs.ai/v1/detect \
>   -H 'Authorization: Bearer $EMPIRIOLABS_API_KEY' \
>   -H 'Content-Type: application/json' \
>   -d '{"model": "gptzero", "input": "The quick brown fox jumps over the lazy dog.", "scan_type": "ai_detection"}'

Parameters

Parameter	Type	Required	Default	Description
`input`	string	no	-	Text to analyze
`scan_type`	enum	no	`"ai_detection"`	AI Detection: detect AI-generated text. Bibliography: analyze citations and references. Sources / Fact Check: find supporting sources for claims in your text. · Allowed: `ai_detection`, `bibliography`, `sources`, `fact_check`
`model_version`	string	no	`"__latest__"`	Select a specific GPTZero model version, or leave as latest for the newest rolling release. Choosing an explicit multilingual release overrides the separate multilingual flag.
`file_url`	string	no	-	URL of a document to scan instead of pasting text. Supported: PDF, DOC, DOCX, RTF, ODT, TXT, MD (max 25 MB). The worker downloads the file and forwards it to GPTZero’s multipart files endpoint. Provide either `input` (text) or `file_url`, not both.
`version`	string	no	`"__latest__"`	Canonical name for model_version. Pin a specific upstream snapshot, or leave as latest for the default rolling alias.
`multilingual`	boolean	no	false	Use GPTZero’s multilingual detection path. Applies to text scans when Model Version is latest; file scans use whichever model version is selected.
`ai_threshold`	number	no	`0.7`	Probability cutoff for flagging sentences as AI-generated. Lower = more sensitive. Range 0.10 to 0.99. · Range: 0.1 – 0.99
`max_sentences`	number	no	`15`	Maximum number of sentences shown in the per-sentence breakdown section. · Range: 1 – 50
`source_sentence`	string	no	-	Optional. The exact sentence or claim you want to find supporting sources for. If left blank, the full input text is used as the claim. (sources / fact_check scan only.)
`max_sources`	number	no	`3`	Maximum number of sources to retrieve for each identified claim. (sources / fact_check scan only.) · Range: 1 – 10
`confidence_threshold`	number	no	`0.5`	Minimum confidence required for a source-match to be returned. Range 0 to 1. (sources / fact_check scan only.) · Range: 0 – 1
`claim_extractor`	string	no	`"claimbuster"`	Method used to extract claims from your text. claimbuster is faster; llm_claim_extractor is more thorough. (sources / fact_check scan only.)
`disable_formatting`	boolean	no	false	Skip the EmpirioLabs Markdown report (per-sentence highlights / scan summary / sources list). The raw upstream GPTZero JSON response is returned.

Notes

File limits

Max 50 files per request
Combined size cap: 15 MB
Each document truncated to 50,000 characters

Supported formats

PDF, DOC, DOCX, TXT, ODT

Machine-readable schema: GET https://api.empiriolabs.ai/v1/models/gptzero.