What actually happened
On 29 September 2026 OpenAI opened the platform it uses to build ChatGPT features. Plugin extensions give a third-party product a sidebar home, interactive panels next to the thread, and viewers for its own file types. Available on all plans. Plugin Creator and a cleaner submission flow sit on top. ChatGPT will recommend plugins in the directory and mid-conversation. Users still approve each plugin’s access.
MCP Events add the other direction. A connected app can notify ChatGPT when something happens and start an automation, including while you are away. OpenAI’s example: watch a project board, read the linked docs, draft a plan. That is on the proposed MCP Events spec, available to all plans.
Separately, Sign in with ChatGPT lets people use their ChatGPT account in other products. Eligible Plus and Pro usage can travel to about 16 launch partners. Sites can host plugins on Business, Enterprise, Healthcare and Edu. An enterprise marketplace is for customers spending part of an OpenAI commitment, not for a five-person shop.
Why a small team cares
If you sell a reporting tool, a project tracker or a client portal, this is a new shelf in a product 1.2 billion people open every week. Discovery inside the chat is the only part that might move pipeline. MCP Events are the operator win: “when a card lands in Notion, start a ChatGPT brief” without standing up your own bot.
If you do not sell software, the change is smaller. You will see more plugin suggestions. You do not need to build anything.
Hype vs useful
This is not an app store with payments and featured placement you can buy. It is a plugin surface plus event webhooks plus a partner sign-in list. Useful this week for a tool vendor with an MCP server already running. Noise this week for everyone else. Do not rebuild your product inside ChatGPT on day two.