May 2026 AI model releases

Last month: https://manifold.markets/prismatic/march-2026-ai-model-releases This market resolves YES for each AI model that receives an official public release during April 2026. A release counts as available to users if it is widely made available through official channels (API, web interface, download, or official partnership). Subvariants are model releases that share the same tier name (e.g., Flash Preview, Flash Live, Flash Instant all count for "Gemini 3.1 Flash"; 5.5-Thinking, 5.5-Instant, 5.5-Nano, 5.5-Pro all count for "GPT5.5"). Releases with a distinct tier name (Flash-Lite, Flash, Pro as a separate tier, etc.) do NOT count for an adjacent tier, even within the same model family. When in doubt, I'll use the official model name the company uses to classify it. Please ask for clarifications. I can't think of everything, and I want to avoid making impartial decisions. Also, if you would like any model to be added, ping me. Notes: Gemini 3.1 Pro Preview and Gemini 3.1 Flash-Lite Preview do not count (were already released before May). A valid model release would either be 3.1 Pro/Flash-Lite General Availability (GA) or 3.2/3.3/3.4/3.5/etc Preview/GA. Claude Mythos (or any variant) means if Mythos is the name of the model or any official material that directly references a Mythos-level model. There may be overlap here with Opus 4.x/5, so be wary!