ChatGPT Space alternatives that work with any agent

Why people look for an alternative

OpenAI launched ChatGPT Space at DevDay on 2026-09-29. It replaces Library and is available on the Pro, Business and Enterprise plans. You create and edit pages on the web and desktop, while mobile can find, read and share pages but not edit them. People with edit access work on a page in real time and can tag ChatGPT, Codex or a dot to make changes. That is a strong fit for teams already paying for ChatGPT. It also sets the boundaries people search around: the work happens inside ChatGPT, collaborative slides and spreadsheets are listed as coming soon, and Keep Updated is not available at launch. As of 2026-09-29, the reviewed OpenAI documentation does not describe a public page API, self-hosting, a choice of non-OpenAI models, or a full-fidelity export of pages.

What to check before you switch

• Which agents can write to it: check whether only the vendor's assistant can edit the work, or whether Claude Code, Codex, Cursor and other MCP clients can too. This decides whether the workspace outlives your current model subscription.
• What the work is made of: a page in a hosted editor and a folder of files behave differently. Files can be versioned, diffed, restored and moved; editor pages depend on the export the vendor offers.
• Plan gate and seat cost: ChatGPT Space needs Pro, Business or Enterprise. Business is $25 per user per month billed monthly, or $20 billed annually, with a two-seat minimum. Price every alternative on the seats who actually edit.
• Source and hosting control: decide whether you need the source code, a self-hosted deployment, or only a vendor you trust. These are separate requirements, and few products meet all three.
• Apps, not only documents: if the result needs a database, logins or a scheduled job, check that the alternative runs apps behind the URL instead of embedding a snapshot in a page.

The shortlist

Grain

Grain is open source under AGPL-3.0, with the source on GitHub, and works with the agent you already use. Your agent writes files; Grain gives them a workspace, a URL, optional Postgres, logins and scheduled jobs. Artifacts are real files you check out, push, checkpoint, restore and export with the CLI. Readers leave comments that the agent can read and act on. A hosted MCP server at https://api.rungrain.com/mcp also works from Claude and ChatGPT, so a ChatGPT user can still write to Grain.

• Fit: people who use more than one agent, or who want agent-built pages, reports and apps kept as files at a stable URL.
• Price model: free for unlimited published artifacts, ten sleeping sandboxes and one always-on workspace, no card required; Pro is $65 per user per month for more always-on workspaces, team seats and custom domains.
• Wins on: open source code, any agent through MCP, and artifacts you can export as files at any time.

Notion AI

Notion is the closest match to the shape of a Space: pages, nested hierarchy, comments, real-time editing and an AI that writes inside the page. Notion lists full Notion AI, including agents and enterprise search, on the Business plan, while Free and Plus include a trial of AI capabilities. It also has databases, which Space pages do not document.

• Fit: teams that want a shared wiki and project docs with AI built in, and do not need ChatGPT specifically.
• Price model: per member per month, with full AI on Business and custom Enterprise pricing.
• Wins on: a mature page editor with relational databases and a large template ecosystem.

Claude Projects and Claude Artifacts

Claude Projects group chats, knowledge files and instructions. On Team and Enterprise plans a project can be shared with organization members as view or edit. Claude Artifacts turn a response into an interactive document or app that can be published. Together they cover much of what a Space does for a team that prefers Claude.

• Fit: teams that standardized on Claude and want shared context plus interactive output in the same product.
• Price model: Projects and Artifacts are on every Claude plan; project sharing and collaboration need Team or Enterprise, priced per seat.
• Wins on: shared project knowledge and instructions for a team that uses Claude as its assistant.

Google Docs with Gemini

If your company already runs on Google Workspace, Docs gives you real-time co-editing, comments and suggestion mode, and Gemini in Docs drafts and revises inside the document. Google lists Gemini in Docs on the Standard, Plus and Enterprise plans, not on Starter.

• Fit: organizations whose documents, email and identity already live in Google Workspace.
• Price model: per user per month as part of a Workspace plan; Gemini in Docs starts at Standard.
• Wins on: no new tool to adopt, and familiar editing, sharing and admin controls.

OpenAgents Workspace

OpenAgents Workspace is the closest open source match to Grain. It is Apache-2.0 licensed, works with Claude Code, Codex, Cursor, Gemini CLI, Aider and other agents, and puts people and agents in shared threads, a synced filesystem, a live browser, shared notes and a task board. It runs in the browser, with desktop and mobile apps, and it can run entirely on your own servers. Pick it when agents working together in chat and tasks matters more than publishing their output as pages and apps.

• Fit: teams that want several agents and people coordinating in one workspace, with a self-hosting path today.
• Price model: not listed on its workspace page as of 2026-09-29; self-hosting is part of the Enterprise offer.
• Wins on: agent coordination (threads, @mentions, task board) and a self-hosting option available now.

AppFlowy

AppFlowy is an open source Notion-style workspace under AGPL-3.0, with pages, databases and AI features. It offers AppFlowy Cloud and a self-hosted option, and its pricing lists add-ons for access to several model providers and for local AI. Pick it when self-hosting a document workspace today matters more than agent integration.

• Fit: teams that want an open source, self-hostable document and database workspace with AI help.
• Price model: free plan for up to two members, paid Pro per user, and optional AI add-ons.
• Wins on: open source and self-hosted document editing available now.

Where Grain fits

Grain fits when the agent does the writing and you want to choose the agent. Run grain init in a folder to write MCP config for Claude Code, Codex and Cursor, let the agent create the page or app, then run grain push, grain checkpoint -m "first version" and grain share --public. The result lives at a URL shaped like https://<slug>.share.rungrain.com. People comment on the result, and the agent reads those comments and makes the next version.

Migration path

1. In ChatGPT Space, copy each page's content and download any saved files you need. As of 2026-09-29, OpenAI does not document a full-fidelity page export, so comments, interactive blocks and edit history may not come with it.
2. Connect Grain's hosted MCP server at https://api.rungrain.com/mcp in ChatGPT, Claude or another MCP client, or run grain init in a local folder for Claude Code, Codex or Cursor.
3. Ask the agent to rebuild each page as files. For an interactive block, ask it to write a working page or app; for data, have it use the workspace's Postgres database.
4. Run grain push and grain checkpoint -m "import from ChatGPT Space", then share with grain share --public or --password <pw>. Open the URL in a signed-out browser to check access.
5. Keep the original space until links and content match. Space sharing roles, inherited access and dot configuration do not carry over.

Frequently asked questions