Ptero

Ptero is a free AI chat platform that provides access to multiple AI models without requiring signup. It supports project-based organization, media attachments, and a code editor; conversations are saved in the user’s browser storage.

Developers can use its OpenAI-compatible REST API with API keys and endpoints for chat completions, models, and usage. The linked GitHub repository describes Ptero as open-source, non-profit software that can be self-hosted or added to WordPress with a shortcode.