OpenAI DevDay 2026: 20+ Announcements, Dots Agents, GPT-6.1 Sol, and the 1.2B-User Line

OpenAI shipped 20+ announcements at DevDay 2026: always-on Dots agents powered by GPT-6 Astra, GPT-6.1 Sol at ~1/5 the per-token cost of Astra, ChatGPT Space shared workspaces, plugin extensions with MCP Events, and a 1.2B weekly users stat.

OpenAI held its 4th annual DevDay at Fort Mason in San Francisco on September 29, 2026, and shipped more than 20 major announcements across ChatGPT, Codex, the agents platform, and pricing. The headline number: ChatGPT is now at 1.2 billion weekly users. The headline products: Dots, always-on AI agents with their own cloud computer; GPT-6.1 Sol, a model that approaches GPT-6 Astra’s intelligence at roughly one-fifth the per-token cost; and ChatGPT Space, a shared workspace where teammates, ChatGPT, and your dot work on the same material.

The three headline launches

Dots are always-on AI agents powered by GPT-6 Astra, each running on its own cloud computer. They’re the headline agent product — designed to take on ongoing responsibilities inside ChatGPT rather than fire in response to a prompt. Availability as of Sep 29: rolling out on Pro, Business Premium, and Enterprise in eligible markets; Enterprise, Edu, and Healthcare beta is admin-enabled and off by default. The shape is closer to Meta’s Muse or SpaceXAI’s Grok Bot than to the agents you invoke from a CLI.

GPT-6.1 Sol is a major upgrade to GPT-6 Sol, which OpenAI released exactly one week before DevDay (September 22). It tracks GPT-6 Astra on agentic coding, computer use, and professional work, at roughly 20% of the per-token cost. Available now in ChatGPT Work and Codex, plus the API as gpt-6.1-sol. Not yet in the consumer Chat surface.

ChatGPT Space is the third launch. A shared workspace where teammates, ChatGPT, and your dot work on the same material. Pages (documents people and agents write together) ship now on Pro, Business, Enterprise. Collaborative slides (multiple people and agents editing the same deck) ship in coming weeks.

The agent and codex platform

The agents story extends past Dots:

  • Agents API with computer use adds computer use, multi-agent orchestration, tool search, tool calling, and context compaction. Available via API and in Codex and ChatGPT Work on Pro 500 and Enterprise.
  • Decisions API is a focused classifier/router built on Luna. Built for fixed-question workflows — routing, triage — where cheap deterministic answers beat chatty reasoning.
  • Codex gains cloud environments, voice control, and a code review surface.
  • MCP Events let plugins start automations when something happens in a connected app. This is the event-driven glue the plugin ecosystem has been missing.

Plugins get the deepest overhaul

Plugins stop being “links in chat.” They now have a home in the ChatGPT sidebar, can build interactive panels and file viewers, and connect to automations via MCP Events. Sites can host plugins (Business, Enterprise, Healthcare, Edu). A Plugin Creator and a redesigned submission flow ship alongside better discovery and ranking. Net effect: plugins become first-class workspace surfaces rather than optional inline tools.

Pricing and tiers

Two new layers:

  • Pro 500 — a new enterprise tier aimed at teams that need Codex + ChatGPT Work + Agents API with computer use. Gated to Pro 500 and Enterprise. Exact list price was not in OpenAI’s recap.
  • Ultrafast — a premium speed option on top of the Pro stack. Per-token premium details weren’t published in the recap.

What was already shipped before the keynote

Most of this was telegraphed. As of Monday, GPT-6 Sol and Luna were already in ChatGPT Work, Codex, and the API. The Agents API docs for durable sessions, multi-agent orchestration, and hosted sandboxes were already live on developers.openai.com. The TestingCatalog leak from September 26 referenced an assistant named “o” — the actual launched product is Dots, not “o.” That’s the lesson of pre-event leaks: code references and UI strings get reported, the launched product is usually the cleaner version.

What’s still missing

The keynote covered the platform and consumer story. Three things OpenAI did not address:

  1. Open weights. Whether GPT-6.1 Sol will eventually drop weights, what happens to GPT-6 Sol, and how the agents ecosystem interacts with the open model world — no clarity today.
  2. Concrete tier pricing. Ultrafast per-token premium, Pro 500 list price, Dots beta access windows for non-Enterprise plans — not in the recap.
  3. AI safety scrutiny context. Altman’s keynote was framed as “we now have an AI research intern.” Mercury News coverage notes the keynote largely avoided mention of security concerns that have dominated OpenAI’s news cycle.

Per the aiidelist.com taxonomy, those three go in the Speculation bucket until OpenAI publishes concrete numbers or statements.

Three takeaways for builders

  1. The agent stack is now the primary platform surface. Dots, Agents API with computer use, MCP Events, and the plugin overhaul all point the same direction. If you’re building agent tooling, OpenAI is the integration target — the chat surface is the shell, not the product.

  2. GPT-6.1 Sol re-prices the agent-economics spreadsheet. A model that approaches Astra at one-fifth the per-token cost is the new benchmark for cost-bottlenecked agent workloads. If your agent cost model assumed GPT-6 Sol pricing, run the numbers again with GPT-6.1 Sol before committing to a deployment.

  3. Plugins are workspace surfaces now. With sidebar homes, interactive panels, MCP Events, and Sites hosting plugins, the plugin surface becomes a workspace. If you have a plugin today, the upgrade path is an MCP Events integration — not just a UI tweak.

The 1.2B weekly users stat is the line that will get quoted in every recap of today’s keynote. It’s also the line that frames what the next year of OpenAI’s product work will be about: distributing work across those 1.2B users via Dots, Space, and the new tiers. The platform story is no longer about ChatGPT. It’s about what runs inside ChatGPT.

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