References to “gpt-5-reasoning-alpha-2025-07-13” have already been spotted on X, with code showing “reasoning_effort: high” in the model configuration. These sightings suggest the model has entered final testing phases, with testers getting their hands on the code and security experts doing red teaming on the model to test vulnerabilities.
Unifying OpenAI’s model lineup
The new model represents OpenAI’s attempt to simplify its increasingly complex product lineup. As Altman explained in February, GPT-5 may integrate features from both the company’s conventional GPT models and its reasoning-focused o-series models into a single system.
“We’re truly excited to not just make a net new great frontier model, we’re also going to unify our two series,” OpenAI’s Head of Develo