# GPTZero > GPTZero is an AI content detection company. Its v2 API analyzes text and documents to detect AI-generated content, returning classification (human / ai / mixed) plus document-, paragraph-, and sentence-level probabilities, perplexity, and burstiness. Authentication is via an X-API-Key header; API access is included with the Professional plan. This llms.txt was generated by the API Evangelist enrichment pipeline from the GPTZero catalog entry and repository artifacts. ## APIs - [GPTZero API v2](https://api.gptzero.me/v2): AI content detection — analyze text, analyze document files, batch analysis, and reports. ## Specs - [OpenAPI 3.0.3 (harvested via Jentic)](https://raw.githubusercontent.com/api-evangelist/gptzero/refs/heads/main/openapi/gptzero-openapi-original.json) ## Docs - [API Documentation (Stoplight)](https://gptzero.stoplight.io/) - [Developer overview](https://gptzero.me/developers) - [Get an API key](https://app.gptzero.me/app/api) - [Rate limit](https://support.gptzero.me/articles/7371584464-what-is-the-rate-limit) - [Release notes (model + API)](https://gptzero.notion.site/GPTZero-Release-Notes-Model-and-API-6f58686f6381498baef35212463b7da6) - [Pricing](https://gptzero.me/pricing) - [Support center](https://support.gptzero.me) ## Operations - analyzeText — POST /predict/text — Analyze text for AI authorship - analyzeDocument — POST /predict/files — Analyze an uploaded document file - createBatchAnalysis — POST /batch — Submit multiple documents asynchronously - getBatchStatus — GET /batch/{batchId} — Check batch status - getBatchResults — GET /batch/{batchId}/results — Retrieve batch results - listReports — GET /reports — List detection reports - getReport — GET /reports/{reportId} — Retrieve a report