OpenAI DevDay 2026: New APIs, GPT-6.1 Sol, and 1.2 Billion ChatGPT Users
OpenAI announced major platform updates at DevDay 2026, including the new Agents API, the Decisions API, the GPT-6.1 Sol reasoning model, and reaching 1.2 billion weekly active ChatGPT users. The release focuses on managed cloud infrastructure for autonomous agents and cost-efficient frontier reasoning. These updates significantly reduce the technical overhead and cost of deploying complex AI agents and automated decision workflows at scale. Reaching 1.2 billion weekly active users reinforces OpenAI's central position in both consumer AI usage and enterprise developer infrastructure. The GPT-6.1 Sol model offers capabilities near Astra for coding and computer use at one-fifth of Astra's API token pricing. Additionally, the Decisions API leverages the Luna model for real-time routing and constrained choices, while the Agents API handles long-running sessions, context compaction, and Model Context Protocol (MCP) integrations.
## BACKGROUND
Building production-grade AI software increasingly requires complex multi-agent orchestration, persistent state management, and lightweight decision logic rather than simple single-prompt completions. OpenAI DevDay is the company's annual conference where it unveils developer platform upgrades, new model variants, and ecosystem tooling.